962/1 stpm chemistry (kimia) · pdf filestpm 962/1 ... koyakkan muka hadapan kertas soalan ini...

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MAJLIS PEPERIKSAAN MALAYSIA (MALAYSIAN EXAMINATIONS COUNCIL)

SIJIL TINGGI PERSEKOLAHAN MALAYSIA (MALAYSIA HIGHER SCHOOL CERTIFICATE)

This question paper consists of printed pages and blank page.

(Kertas soalan ini terdiri daripada halaman bercetak dan halaman kosong.)

© Majlis Peperiksaan Malaysia

STPM 962/1

For examiner‟s use

(Untuk kegunaan

pemeriksa)

Section B

(Bahagian B)

16

17

Section C

(Bahagian C)

Total

(Jumlah)

Instructions to candidates:

DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE

TOLD TO DO SO. There are fifteen questions in Section A. For each question, four choices

of answers are given. Choose one correct answer and indicate it on the Multiple-choice Answer Sheet provided. Read the instructions on the

Multiple-choice Answer Sheet very carefully. Answer all questions. Marks

will not be deducted for wrong answers. Answer all questions in Section B. Write your answers in the spaces

provided.

Answer any two questions in Section C. All essential working should be shown. For numerical answers, unit should be quoted wherever appropriate.

Begin each answer on a fresh sheet of paper and arrange your answers in numerical order.

Tear off the front page of this question paper and your answer sheets of

Section B, and tie both of them together with your answer sheets of Section C. Answers may be written in either English or Bahasa Malaysia.

Ple

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Arahan kepada calon:

JANGAN BUKA KERTAS SOALAN INI SEHINGGA ANDA DIBENARKAN BERBUAT

DEMIKIAN.

Ada lima belas soalan dalam Bahagian A. Bagi setiap soalan, empat pilihan jawapan diberikan. Pilih satu jawapan yang betul dan tandakan jawapan itu pada Borang Jawapan Aneka Pilihan yang

dibekalkan. Baca arahan pada Borang Jawapan Aneka Pilihan itu dengan teliti. Jawab semua soalan.

Markah tidak akan ditolak bagi jawapan yang salah. Jawab semua soalan dalam Bahagian B. Tulis jawapan anda di ruang yang disediakan.

Jawab mana-mana dua soalan dalam Bahagian C. Semua jalan kerja yang sesuai hendaklah ditunjukkan. Bagi jawapan berangka, unit hendaklah dinyatakan di mana-mana yang sesuai. Mulakan

setiap jawapan pada helaian kertas jawapan yang baharu dan susun jawapan anda mengikut tertib

berangka. Koyakkan muka hadapan kertas soalan ini dan helaian jawapan anda bagi Bahagian B, dan ikatkan

kedua-duanya bersama-sama dengan helaian jawapan anda bagi Bahagian C.

Jawapan boleh ditulis dalam bahasa Inggeris atau Bahasa Malaysia.

- 1 -

www.myschoolchildren.commore examination papers at :

SPECIMEN PAPER (bilingual) 962/1 STPM

CHEMISTRY (KIMIA)

PAPER 1 (KERTAS 1)

Section A [15 marks]

Answer all questions in this section.

1 Which particle has the correct corresponding number of electrons and number of neutrons?

Particle Number of electrons Number of neutrons

A N167 9 7

B 218

8 O 8 10

C F199 19 9

D Br7935 34 44

2 The mass spectrum of an element X is shown below.

From the mass spectrum above, it can be concluded that,

A the nucleon number of X is 14.5

B the relative molecular mass of X2 is 29

C the isotopes of X have a different number of protons

D element X consists of two isotopes with relative isotopic mass of 14 and 15

3 What is the maximum number of emission lines possible for a hydrogen atom with electronic

energy levels n = 1, n = 2 and n = 3?

A 2 B 3 C 4 D 6

4 Which compound is not ionic?

A CaCl2 B SiCl4 C Al2O3 D Mg3N2

5 Which molecule possesses polar bonds but its overall molecular dipole moment is zero?

A NH3 B H2S C CCl4 D CH3Cl

962/1

100 99.63

14 15 Mass/charge 0

Percentage

of abundance

0.37

- 2 -


Bahagian A [15 markah]

Jawab semua soalan dalam bahagian ini.

1 Zarah yang manakah yang mempunyai padanan yang betul dengan nombor elektron dan nombor

neutron?

Zarah Nombor elektron Nombor neutron

A N167 9 7

B 218

8 O 8 10

C F199 19 9

D Br7935 34 44

2 Spektrum jisim unsur X ditunjukkan di bawah.

Daripada spektrum jisim di atas, dapat disimpulkan bahawa

A nombor nukleon X ialah 14.5

B jisim molekul relatif X2 ialah 29

C isotop X mempunyai nombor proton yang berbeza

D unsur X terdiri daripada dua isotop dengan jisim isotop relatif 14 dan 15

3 Berapakah bilangan garisan pemancaran maksimum yang mungkin bagi atom hidrogen dengan

aras tenaga elektronik n = 1, n = 2, dan n = 3?

A 2 B 3 C 4 D 6

4 Sebatian yang manakah yang tidak ionik?

A CaCl2 B SiCl4 C Al2O3 D Mg3N2

5 Molekul yang manakah yang mempunyai ikatan berkutub tetapi jumlah momen dwikutubnya

molekulnya adalah sifar?

A NH3 B H2S C CCl4 D CH3Cl

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100 99.63

14 15 Jisim/cas 0

Peratusan

kelimpahan

0.37

- 3 -


6 Which statement regarding metallic bond is correct?

A The metallic bond enables metals to be a good conductor of heat.

B The strength of the metallic bond depends on the size of the atom of the metal.

C The metallic bonds are formed because metals have relatively high ionisation energies.

D The metallic bond is formed from the attraction between the electrons and the nucleus in the

atom.

7 A mixture of 8.0 g of a monoatomic gas X and an unknown quantity of mass of diatomic gas Y

has a volume of V m3 at s.t.p. When 20.0 g of gas X is added to the mixture under the same

conditions, the volume of the mixture is 2V m3. What is the quantity of gas Y in the mixture?

[Relative atomic masses of X and Y are 4 and 1 respectively. Assume that gas X does not react

with gas Y.]

A 1 g B 2 g C 5 g D 6 g

8 Boron nitride, BN, can exist in two different forms P and Q. P has a layered giant molecular

lattice with weak forces between the layers. Q has a giant lattice in which each atom is bonded to

another by four covalent bonds. The following statements are regarding P and Q.

I P and Q have high melting points.

II P and Q have the same density.

III Structure Q is harder than structure P.

IV Structure Q conducts electricity in molten state.

Which statements about P and Q are correct?

A I and II

B I and III

C II and IV

D III and IV

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6 Penyataan yang manakah yang betul tentang ikatan logam?

A Ikatan logam membolehkan logam menjadi konduksi haba yang baik.

B Kekuatan ikatan logam bergantung kepada saiz atom logam itu.

C Ikatan logam yang terbentuk disebabkan logam mempunyai tenaga pengionan yang tinggi

secara relatifnya.

D Ikatan logam terbentuk daripada penarikan antara elektron dengan nuklues dalam atom.

7 Satu campuran 8.0 g gas monoatom X dan satu kuantiti gas dwiatom Y yang tidak diketahui

jisimnya mempunyai isi padu V m3 pada s.t.p. Apabila 20.0 g gas X ditambahkan kepada campuran

itu pada keadaan yang sama, isi padu campuran itu ialah 2V m3. Berapakah kuantiti gas Y dalam

campuran itu?

[Jisim atom relatif bagi X dan Y masing-masing ialah 4 dan 1. Anggap bahawa gas X tidak

bertindak balas dengan gas Y.]

A 1 g B 2 g C 5 g D 6 g

8 Boron nitrida, BN, boleh wujud dalam dua bentuk yang berbeza, P dan Q. P mempunyai lapisan

kekisi molekul raksasa dengan daya yang lemah antara lapisan. Q mempunyai kekisi raksasa yang

mana setiap atom terikat kepada atom yang lain oleh empat ikatan kovalen. Penyataan yang berikut

berkaitan dengan P dan Q.

I P dan Q mepunyai takat lebur yang tinggi

II P dan Q mempunyai ketumpatan yang sama

III Struktur Q lebih keras daripada struktur P

IV Struktur Q mengkonduksi elektik dalam keadaan leburan

Penyataan yang manakah yang betul tentang P dan Q?

A I dan II

B I dan III

C II dan IV

D III dan IV

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- 5 -


9 The distribution of molecular kinetic energy of a gas at 279 K and 289 K is shown by the

Maxwell-BØltzman graph below.

Which statement best explains why the rate of reaction in a gas sample at 279 K increases two

folds when the temperature is increased to 289 K?

A The number of collisions increases two fold.

B The total area under the curve increases two fold.

C The average velocity of the molecules increases two fold.

D The numbers of molecules with energy equal to or greater than Ea increases two fold.

10 The Arrhenius equation is given as k = .

aE

RTAe A reaction occurs 27 times faster at 52 C than at

22 C. What is the activation energy for this reaction?

[Gas constant, R, is 8.31 J K1 mol

1]

A 1.04 kJ mol1 B 10.5 kJ mol

1 C 38.1 kJ mol

1 D 87.5 kJ mol

1

11 A reversible reaction can be represented by the equation:

P + Q R + S

when the system is in equilibrium,

A the masses P, Q, R and S are the same

B the reactions in both directions stopped

C the concentrations of P, Q, R and S are the same

D the concentrations of P, Q, R and S are always constant

12 The equilibrium constant, Kp, for the decomposition of calcium carbonate,

CaCO3(s) CaO(s) + CO2(g)

is 1.6 1023

atm at 298 K and 6.3 1011

atm at 500 K. Which statement is true of the

decomposition?

A The forward reaction is endothermic.

B Kp depends on the mass of CaCO3 used.

C The rate of forward reaction decreases as the temperature increases.

D The activation energy of forward reaction increases as the temperature increases.

962/1

Kinetic energy

Number of

molecules

- 6 -


9 Taburan tenaga kinetik bagi gas pada 279 K dan 289 K ditunjukkan dalam graf Maxwell-

BØltzman di bawah.

Penyataan yang manakah yang paling baik menerangkan mengapa kadar tindak balas dalam

sampel gas pada 279 K bertambah dua kali ganda apabila suhu dinaikkan kepada 289 K?

A Bilangan perlanggaran bertambah dua kali ganda.

B Jumlah luas kawasan di bawah lengkung bertambah dua kali ganda.

C Halaju purata molekul bertambah dua kali ganda.

D Bilangan molekul dengan tenaga yang sama atau lebih besar daripada Ea bertambah dua kali

ganda.

10 Persamaan Arrhenius diberikan sebagai k = .

aE

RTAe Satu tindak balas berlaku 27 lebih cepat pada

52 C berbanding 22 C. Berapakah tenaga pengaktifan bagi tindak balas ini?

[Pemalar gas, R ialah 8.31 J K1 mol

1]

A 1.04 kJ mol1 B 10.5 kJ mol

1 C 38.1 kJ mol

1 D 87.5 kJ mol

1

11 Suatu tindak balas berbalik boleh diwakili dengan persamaan:

P + Q R + S

apabila sistem itu dalam keadaan keseimbangan,

A jisim P, Q, R, dan S adalah sama

B tindak balas dalam kedua-dua arah dihentikan

C kepekatan P, Q, R, dan S adalah sama

D kepekatan P, Q, R, dan S sentiasa malar

12 Pemalar keseimbangan, Kp, bagi penguraian kalsium karbonat,

CaCO3(p) CaO(p) + CO2(g)

ialah 1.6 1023

atm pada 298 K dan 6.3 1011

atm pada 500 K. Penyataan yang manakah yang

betul tentang penguraian itu?

A Tindak balas ke hadapan adalah endotermik.

B Kp bergantung pada jisim CaCO3 yang digunakan.

C Kadar tindak balas ke hadapan berkurang apabila suhu bertambah.

D Tenaga pengaktifan bagi tindak balas ke hadapan bertambah apabila suhu bertambah.

962/1

Tenaga kinetik

Bilangan

molekul

- 7 -


13 In the reaction Cu2+

+ 4NH3 [Cu(NH3)4]2+

, the Cu2+

ion acts as a

A Lewis acid

B Lewis base

C BrØnsted-Lowry acid

D BrØnsted-Lowry base

14 The following quantities may change when 0.10 mol dm−3

ethanoic acid is diluted with water at

298 K.

I Acid dissociation constant

II pH value

III Degree of dissociation

IV Ionic product of water

Which quantities will change?

A I and II

B I and IV

C II and III

D III and IV

15 The graph below shows the variation of pH for the titration of 25.0 cm3 of 0.2 mol dm

3 aqueous

ammonia solution with 0.2 mol dm3 hydrochloric acid.

Which part of the above graph shows the mixture of ammonia and hydrochloric acid that can be

used as buffer solution?

A p B q C r D s

962/1

Volume of HCl added/cm3

pH

- 8 -


13 Dalam tindak balas, Cu2+

+ 4NH3 [Cu(NH3)4]2+

, ion Cu2+

bertindak sebagai

A asid Lewis

B bes Lewis

C asid BrØnsted-Lowry

D bes BrØnsted-Lowry

14 Kuantiti yang berikut boleh berubah apabila asid etanoik 0.10 mol dm−3

dicairkan dengan air pada

298 K.

I Pemalar penceraian asid

II Nilai pH

III Darjah penceraian

IV Hasil darab ion bagi air

Kuantiti yang manakah yang akan berubah?

A I dan II

B I dan IV

C II dan III

D III dan IV

15 Graf di bawah menunjukkan ubahan pH bagi pentitratan 25.0 cm3 larutan akueus ammonia

0.2 mol dm3 dengan asid hidroklorik 0.2 mol dm

3.

Bahagian yang manakah pada graf di atas yang menunjukkan campuran ammonia dan asid

hidroklorik boleh digunakan sebagai larutan penimbal?

A p B q C r D s

962/1

Isi padu HCl ditambah/cm3

pH

- 9 -


Section B [15 marks]


16 Beams of particles from different sources are passed through an electric field. The path of the

beam of sub-atomic particles Y through the electric field is shown in the diagram below.

(a) (i) Name the subatomic particles Y. [1 mark]

....................................................................................................................................................................

(ii) Draw the paths of the beams of electrons and hydrogen ions in the above diagram.

[2 marks]

(iii) If a beam of deuterium ions is passed through the electric field, explain the difference in

deflection angle between the beam of hydrogens ions and that of deuterium ions. [2 marks]

....................................................................................................................................................................

....................................................................................................................................................................

(b) P+ and Q

– ions are isoelectronic with the

4018 X isotope.

(i) State the nucleon number of the 4018 X isotope. [1 mark]

....................................................................................................................................................................

(ii) Identity P+ and Q

– ions. [2 marks]

....................................................................................................................................................................

....................................................................................................................................................................

962/1

+

Source of particles

–

- 10 -


Bahagian B [15 markah]


16 Alur-alur zarah dari sumber-sumber yang berlainan dilalukan menerusi suatu medan elektrik.

Laluan alur zarah subatom Y menerusi medan elektrik ditunjukkan dalam gambar rajah di bawah.

(a) (i) Namakan zarah subatom Y itu. [1 markah]

....................................................................................................................................................................

(ii) Lukis laluan alur elektron dan ion hidrogen pada gambar rajah di atas. [2 markah]

(iii) Jika alur ion deuterium dilalukan melalui medan elektrik tersebut, jelaskan perbezaan

sudut pesongan antara alur ion hidrogen dengan alur ion deuterium. [2 markah]

....................................................................................................................................................................

....................................................................................................................................................................

(b) Ion P+ and ion Q

– adalah isoelektronik dengan isotop

4018 .X

(i) Nyatakan nombor nukleon bagi isotop 4018 .X [1 markah]

....................................................................................................................................................................

(ii) Kenal pasti ion P+ dan ion Q

–. [2 markah]

....................................................................................................................................................................

....................................................................................................................................................................

962/1

+

Sumber zarah

–

Sil

a k

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kkan d

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panja

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ari

s putu

s-p

utu

s in

i.

- 11 -


17 The table below shows the temperature and pressure of critical point and triple point of substance

X.

Temperature/ C Pressure/atm

Critical point 31 73

Triple point –57 5

At atmospheric pressure, X sublimes at –78 C. The freezing point of X increases by 2 C for

every 10 atm increase in pressure.

(a) Using the above information, sketch and label the phase diagram of X. [4 marks]

(b) Why does the freezing point of X increase with pressure? [1 mark]

....................................................................................................................................................................

(c) Solid X is known as dry ice.

(i) How is liquid X produced from dry ice? [1 mark]

....................................................................................................................................................................

(ii) State an industrial use for dry ice. [1 mark]

....................................................................................................................................................................

962/1

- 12 -


17 Jadual di bawah menunjukkan suhu dan tekanan bagi takat genting dan takat ganda tiga bahan X.

Suhu/ C Tekanan/atm

Takat genting 31 73

Takat ganda tiga –57 5

Pada tekanan atmosfera, X memejalwap pada suhu –78 C. Takat beku X bertambah sebanyak

2 C bagi setiap pertambahan tekanan 10 atm.

(a) Menggunakan maklumat di atas, lakar dan label gambar rajah fasa X. [4 markah]

(b) Mengapakah takat beku X bertambah dengan tekanan? [1 markah]

....................................................................................................................................................................

(c) Pepejal X dikenal sebagai ais kering.

(i) Bagaimanakah cecair X dihasilkan daripada ais kering? [1 markah]

....................................................................................................................................................................

(ii) Nyatakan satu kegunaan industri ais kering. [1 markah]

....................................................................................................................................................................

962/1

Sil

a k

oya

kka

n d

i se

pa

nja

ng g

ari

s p

utu

s-p

utu

s in

i.

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Section C [30 marks]

Answer any two questions in this section.

18 (a) Water is a hydride of oxygen. The bonding in water molecules is a result of the overlapping of

the orbitals of oxygen and hydrogen atoms.

(i) What is meant by orbitals? [1 mark]

(ii) Draw a labelled diagram illustrating the shapes of all the orbitals of an oxygen atom

with quantum number n = 2. [3 marks]

(iii) Draw a labelled diagram to illustrate the overlapping of orbitals in a water molecule.

[3 marks]

(b) Draw the Lewis structures for ion I3 and molecule SF6, and state their geometries. [4 marks]

State why

(i) compound SF6 is used as an insulating gas in high voltage electrical appliances,

[1 mark]

(ii) compound SI6 does not exist, [1 mark]

(iii) I3 and Br3 ions exist but F3 ion does not exist under normal conditions. [2 marks]

19 Aqueous chlorine dioxide solution reacts with an alkaline solution according to the following

equation.

2ClO2(aq) + 2OH (aq) ClO3 (aq) + ClO2 (aq) + H2O(l)

(a) Determine the oxidation number of chlorine in ClO2 and ClO3 . [2 marks]

(b) The results of the kinetic experiment of the reaction of aqueous chlorine dioxide solution are

shown in the table below.

Experiment

number

[ClO2]/

mol dm3

[OH ]/

mol dm3

Initial rate/

mol dm3 s

1

1 0.0575 0.0216 8.21 × 103

2 0.0713 0.0216 1.26 × 102

3 0.0575 0.0333 1.26 × 102

(i) Determine the order of the reaction. [7 marks]

(ii) Calculate the rate constant, k, for the reaction. [2 marks]

(iii) Calculate the pH of the aqueous chlorine dioxide solution, if its concentration is

0.100 mol dm3 and the initial rate of the disproportionation reaction is 3.56 × 10

2 mol dm

3 s

1.

[4 marks]

962/1

- 14 -


Bahagian C [30 markah]

Jawab mana-mana dua soalan dalam bahagian ini.

18 (a) Air ialah hidrida oksigen. Ikatan dalam molekul air terhasil melalui pertindihan orbital atom

oksigen dengan atom hidrogen.

(i) Apakah yang dimaksudkan dengan orbital? [1 markah]

(ii) Lukis gambar rajah berlabel yang mengilustrasikan bentuk semua orbital bagi atom

oksigen dengan nombor kuantum n = 2. [3 markah]

(iii) Lukis gambar rajah berlabel untuk mengilustrasi pertindihan orbital dalam molekul air.

[3 markah]

(b) Lukis struktur Lewis bagi ion I3 dan molekul SF6, dan nyatakan geometri bagi ion I3 dan

molekul SF6. [4 markah]

Nyatakan mengapa

(i) sebatian SF6 digunakan sebagai gas penebat dalam alat-alat elektrik bervoltan tinggi,

[1 markah]

(ii) sebatian SI6 tidak wujud, [1 markah]

(iii) ion I3 dan ion Br3 wujud tetapi ion F3 tidak wujud dalam keadaan biasa. [2 markah]

19 Larutan klorin dioksida akueus bertindak balas dengan larutan beralkali mengikut persamaan yang

berikut.

2ClO2(ak) + 2OH (ak) ClO3 (ak) + ClO2 (ak) + H2O(c)

(a) Tentukan nombor pengoksidaan klorin dalam ClO2 dan ClO3 . [2 markah]

(b) Keputusan uji kaji kinetik dalam tindak balas larutan akueus klorin dioksida ditunjukkan

dalam jadual di bawah.

Nombor

uji kaji

[ClO2]/

mol dm3

[OH ]/

mol dm3

Kadar awal/

mol dm3 s

1

1 0.0575 0.0216 8.21 × 103

2 0.0713 0.0216 1.26 × 102

3 0.0575 0.0333 1.26 × 102

(i) Tentukan tertib tindak balas itu. [7 markah]

(ii) Hitung pemalar kadar, k, bagi tindak balas itu. [2 markah]

(iii) Hitung pH larutan akueus klorin dioksida, jika kepekatannya ialah 0.100 mol dm3 dan

kadar awal tindak balas penyahkadarannya ialah 3.56 × 102 mol dm

3 s

1. [4 markah]

962/1

- 15 -


20 (a) The Haber process is used in the industrial production of ammonia. The equation for the

reaction is as follows.

N2(g) + 3H2(g) 2NH3(g) H = 92 kJ mol1

An analysis of an equilibrium mixture obtained from the mixing of gaseous nitrogen and

hydrogen shows a composition of 40% of ammonia when the total pressure of the system is 20 atm.

(i) Determine the mole fraction of nitrogen, hydrogen and ammonia. [3 marks]

(ii) Calculate the partial pressures for nitrogen, hydrogen and ammonia. [2 marks]

(iii) Calculate the equilibrium constant, Kp, for the equilibrium. [2 marks]

(b) In an experiment, 0.100 moles of dinitrogen tetraoxide gas is allowed to dissociate to nitrogen

dioxide gas in a 1.0 dm3 container at 383 K. The graph of concentrations of both gases against time is

shown below.

(i) Calculate the equilibrium constant, Kc, for the above reaction at 383 K. [4 marks]

(ii) Calculate the pressure in the container after the system had attained equilibrium at

383 K. [4 marks]

[Gas constant, R, is 8.31 J K1 mol

1.]

962/1

Time/min

Concentration/

mol dm3

- 16 -


20 (a) Proses Haber digunakan dalam penghasilan industri ammonia. Persamaan bagi tindak balas

adalah seperti yang berikut.

N2(g) + 3H2(g) 2NH3(g) H = 92 kJ mol1

Analisis suatu campuran keseimbangan yang diperoleh daripada campuran gas nitrogen dan

hidrogen menunjukkan komposisi ammonia 40% apabila jumlah tekanan sistem adalah 20 atm.

(i) Tentukan pecahan mol nitrogen, hidrogen, dan ammonia. [3 markah]

(ii) Hitung tekanan separa bagi nitrogen, hidrogen, dan ammonia. [2 markah]

(iii) Hitung pemalar keseimbangan, Kp, untuk keseimbangan itu. [2 markah]

(b) Dalam satu uji kaji, 0.100 mol gas dinitrogen tetraoksida dibiarkan tercerai kepada gas

nitrogen dioksida di dalam bekas 1.0 dm3 pada 383 K. Graf kepekatan kedua-dua gas itu lawan masa

ditunjukkan di bawah.

(i) Hitung pemalar keseimbangan, Kc, bagi tindak balas di atas pada 383 K. [4 markah]

(ii) Hitung tekanan dalam bekas selepas sistem mencapai keseimbangan pada 383 K.

[4 markah]

[Pemalar gas, R, ialah 8.31 J K1 mol

1.]

962/1

Masa/min

Kepekatan/

mol dm3

- 17 -




SPECIMEN PAPER

962/2 STPM

CHEMISTRY (KIMIA)

PAPER 2 (KERTAS 2)







STPM 962/2


(Untuk kegunaan

pemeriksa)

Section B

(Bahagian B)

16

17

Section C

(Bahagian C)

Total

(Jumlah)



TOLD TO DO SO.

There are fifteen questions in Section A. For each question, four choices

of answers are given. Choose one correct answer and indicate it on the Multiple-choice Answer Sheet provided. Read the instructions on the

Multiple-choice Answer Sheet very carefully. Answer all questions. Marks will not be deducted for wrong answers.

Answer all questions in Section B. Write your answers in the spaces

provided. Answer any two questions in Section C. All essential working should be

shown. For numerical answers, unit should be quoted wherever appropriate.

Begin each answer on a fresh sheet of paper and arrange your answers in numerical order.

Tear off the front page of this question paper and your answer sheets of Section B, and tie both of them together with your answer sheets of Section C.

Answers may be written in either English or Bahasa Malaysia.

Ple

ase

tea

r off

alo

ng t

he

per

fora

ted l

ine.

(Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-putu

s in

i.)



DEMIKIAN.

Ada lima belas soalan dalam Bahagian A. Bagi setiap soalan, empat pilihan jawapan diberikan. Pilih satu jawapan yang betul dan tandakan jawapan itu pada Borang Jawapan Aneka Pilihan yang

dibekalkan. Baca arahan pada Borang Jawapan Aneka Pilihan itu dengan teliti. Jawab semua soalan. Markah tidak akan ditolak bagi jawapan yang salah.

Jawab semua soalan dalam Bahagian B. Tulis jawapan anda di ruang yang disediakan.

Jawab mana-mana dua soalan dalam Bahagian C. Semua jalan kerja yang sesuai hendaklah ditunjukkan. Bagi jawapan berangka, unit hendaklah dinyatakan di mana-mana yang sesuai. Mulakan

setiap jawapan pada helaian kertas jawapan yang baharu dan susun jawapan anda mengikut tertib

berangka.

Koyakkan muka hadapan kertas soalan ini dan helaian jawapan anda bagi Bahagian B, dan ikatkan

kedua-duanya bersama-sama dengan helaian jawapan anda bagi Bahagian C. Jawapan boleh ditulis dalam bahasa Inggeris atau Bahasa Malaysia.

- 18 -




1 Which equation represents the enthalpy of atomisation of sodium?

A Na(s) Na(g)

B Na(l) Na(g)

C Na(l) Na+(g) + e

D Na(g) Na+(g) + e

2 The diagram below shows the Born-Haber cycle for the formation of sodium fluoride.

Na(s) + ½F2(g) NaF(s)

+107 kJ mol1 +79 kJ mol

1

Na(g) F(g) 928 kJ mol1

+496 kJ mol1

Na+(g) + F (g)

What is the electron affinity of fluorine?

A 820 kJ mol1 B 328 kJ mol

1 C 275 kJ mol

1 D 246 kJ mol

1

3 Which cation has the highest hydration energy?

A Li+ B Na

+ C K

+ D Rb

+

962/2

574 kJ mol1

- 19 -




1 Persamaan yang manakah yang mewakili entalpi pengatoman natrium?

A Na(p) Na(g)

B Na(c) Na(g)

C Na(c) Na+(g) + e

D Na(g) Na+(g) + e

2 Gambar rajah di bawah menunjukkan kitar Born-Haber bagi pembentukan natrium fluorida.

Na(p) + ½F2(g) NaF(p)

+107 kJ mol1 +79 kJ mol

1

Na(g) F(g) 928 kJ mol1

+496 kJ mol1

Na+(g) + F (g)

Berapakah afiniti elektron fluorin?

A 820 kJ mol1 B 328 kJ mol

1 C 275 kJ mol

1 D 246 kJ mol

1

3 Kation yang manakah yang mempunyai tenaga penghidratan paling tinggi?

A Li+ B Na

+ C K

+ D Rb

+

962/2

574 kJ mol1

- 20 -


4 The standard reduction potentials, E , for oxygen and manganese are as follows.

Electrode system E /V

O2(g), H+(aq), H2O2(aq) Pt(s) +0.68

MnO4 (aq), H+(aq), Mn

2+(aq) Pt(s) +1.52

The chemical cell constructed by combining the two half-cells above may have the following

results.

I Mn2+

ion undergoes reduction to form MnO4 ion.

II H2O2 undergoes oxidation to form O2.

III The platinum electrode for oxygen half-cell is the positive electrode.

IV The e.m.f. of the cell is +0.84 V.

Which of the above statements are true for the chemical cell formed?

A I and II

B I and III

C II and IV

D III and IV

5 The graph below shows the standard reduction potentials, E , for the half-cell reactions of five

elements, P, Q, R, S and T.

It can be concluded that from P to T,

A the electronegativity of the elements increases

B the chemical reactivity of the elements decreases

C the strength of the elements as reducing agents increases

D the strength of the elements as oxidising agents increases

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E /V

Element

- 21 -


4 Keupayaan penurunan piawai, E , bagi oksigen dan mangan adalah seperti yang berikut.

Sistem elektrod E /V

O2(g), H+(ak), H2O2(ak) Pt(p) +0.68

MnO4 (ak), H+(ak), Mn

2+(ak) Pt(p) +1.52

Sel kimia yang dibina daripada gabungan dua setengah sel di atas mungkin mempunyai keputusan

yang berikut.

I Ion Mn2+

mengalami penurunan untuk membentuk ion MnO4 .

II H2O2 mengalami pengoksidaan untuk membentuk O2.

III Elektrod platinum bagi setengah sel oksigen ialah elektrod positif.

IV D.g.e. sel ialah +0.84 V.

Penyataan di atas yang manakah yang benar bagi sel kimia yang terbentuk?

A I dan II

B I dan III

C II dan IV

D III dan IV

5 Graf di bawah menunjukkan keupayaan penurunan piawai, E , bagi tindak balas setengah sel lima

unsur, P, Q, R, S, dan T.

Dapat disimpulkan bahawa daripada P hingga T,

A keelektronegatifan unsur-unsur bertambah

B kereaktifan kimia unsur-unsur berkurang

C kekuatan unsur-unsur sebagai agen penurunan bertambah

D kekuatan unsur-unsur sebagai agen pengoksidaan bertambah

962/2

E /V

Unsur

- 22 -


6 The standard reduction potentials, E , for several copper and iron species are given below.

Electrode system E /V

Cu2+

(aq)/Cu+(aq) +0.15

Cu2+

(aq)/Cu(s) +0.34

Cu+(aq)/Cu(s) +0.52

Fe2+

(aq)/Fe(s) 0.44

Fe3+

(aq)/Fe(s) 0.04

Fe3+

(aq)/Fe2+

(aq) +0.77

Which statement regarding the species is correct?

A Cu(s) is the strongest reducing agent.

B Fe3+

(aq) is the strongest oxidising agent.

C Cu2+

(aq) is able to oxidise Fe2+

(aq) to Fe3+

(aq).

D The e.m.f. of the cell Fe(s) Fe2+

(aq) Cu+(aq) Cu(s) is 0.08 V.

7 A molten compound consisting of the elements X and Y is electrolysed using a current of 1.00 A

for 1930 seconds. 2.07 g of X is formed at the cathode and 1.60 g of Y is formed at the anode. What

is the correct empirical formula for the compound?

[Relative atomic masses for X and Y are 207.0 and 80.0 respectively; Faraday‟s constant, F, is

96 500 C mol1.]

A XY B XY2 C X2Y D X2Y2

8 Across Period 3 of the Periodic Table, from sodium to chlorine

A the electronegativity of the elements decreases

B the ionisation energy of the elements decreases

C the standard reduction potential of the elements increases

D the strength of the elements as reducing agents increases

9 The solubilities of two sulphates of Group 2 elements in the Periodic Table are given below.

Compound Solubility (g per 100 g)

at 20 C

CaSO4 2.3 101

BaSO4 2.3 104

Which statement best explains the above data?

A The size of Ba2+

ion is bigger than that of Ca2+

ion.

B Barium has a lower ionisation energy than calcium.

C BaSO4 has a lower lattice energy than CaSO4.

D Ba2+

ion has a lower hydration energy than Ca2+

ion.

962/2

- 23 -


6 Keupayaan penurunan piawai, E , bagi beberapa spesis kuprum dan ferum diberikan di bawah.

Sistem elektrod E /V

Cu2+

(ak)/Cu+(ak) +0.15

Cu2+

(ak)/Cu(p) +0.34

Cu+(ak)/Cu(p) +0.52

Fe2+

(ak)/Fe(p) 0.44

Fe3+

(ak)/Fe(p) 0.04

Fe3+

(ak)/Fe2+

(ak) +0.77

Penyataan yang manakah yang betul tentang spesis itu?

A Cu(p) ialah agen penurunan yang paling kuat.

B Fe3+

(ak) ialah agen pengoksidaan yang paling kuat.

C Cu2+

(ak) boleh mengoksida Fe2+

(ak) kepada Fe3+

(ak).

D D.g.e sel Fe(p) Fe2+

(ak) Cu+(ak) Cu(p) ialah 0.08 V.

7 Satu sebatian lebur yang terdiri daripada unsur X dan Y telah dielektrolisiskan menggunakan arus

1.00 A selama 1930 saat. Sebanyak 2.07 g X terbentuk di katod dan 1.60 g Y terbentuk di anod.

Apakah formula empirik yang betul bagi sebatian itu?

[Jisim atom relatif bagi X dan Y masing-masing ialah 207.0 dan 80.0; Pemalar Faraday, F, ialah

96 500 C mol1.]

A XY B XY2 C X2Y D X2Y2

8 Merentasi Kala 3 Jadual Berkala, daripada natrium ke klorin

A keelektronegatifan unsur berkurang

B tenaga pengionan unsur berkurang

C keupayaan penurunan piawai unsur bertambah

D kekuatan unsur sebagai agen penurunan bertambah

9 Keterlarutan dua sulfat unsur Kumpulan 2 dalam Jadual Berkala diberikan di bawah.

Sebatian Keterlarutan (g per 100 g)

pada 20 C

CaSO4 2.3 101

BaSO4 2.3 104

Penyataan yang manakah yang paling tepat menjelaskan data di atas?

A Saiz ion Ba2+

lebih besar daripada ion Ca2+

.

B Barium mempunyai tenaga pengionan yang lebih rendah daripada kalsium.

C BaSO4 mempunyai tenaga kekisi yang lebih rendah daripada CaSO4.

D Ion Ba2+

mempunyai tenaga penghidratan lebih rendah daripada ion Ca2+

.

962/2

- 24 -


10 A tetrachloride of Group 14, XCl4, of the Periodic Table is thermally unstable and easily

hydrolysed. It decomposes at room temperature according the equation:

XCl4 XCl2 + Cl2

What is X ?

A Carbon B Silicon C Germanium D Lead

11 Which statement is true of the oxides of Group 14 elements of the Periodic Table?

A All the oxides have covalent bonds.

B The oxides with +4 oxidation state can react with alkalis.

C The oxides with +4 oxidation state are more stable down the group.

D The acidity of the oxides with +2 oxidation state increases down the group.

12 An aqueous solution of X, a mixture of two compounds, has the following properties.

(i) Decomposes in the presence of light to form a gas.

(ii) Reacts with aqueous barium hydroxide to form salt and water.

(iii) Reacts with aqueous silver nitrate to form a precipitate which can dissolve in aqueous

ammonia.

The following compounds may be found in an aqueous solution of X.

I HCl

II HBr

III HOCl

IV NH4Cl

What could X be?

A I and II

B I and III

C II and IV

D III and IV

13 Halogens or their compounds are not used

A as detergents

B in photography

C as propellant in aerosol

D in the sterilisation of water

962/2

- 25 -


10 Satu tetraklorida Kumpulan 14, XCl4, Jadual Berkala tidak stabil secara terma dan mudah

terhidrolisis. Tetraklorida itu terurai pada suhu bilik mengikut persamaan:

XCl4 XCl2 + Cl2

Apakah X ?

A Karbon B Silikon C Germanium D Plumbum

11 Penyataan yang manakah yang benar tentang oksida unsur Kumpulan 14 Jadual Berkala?

A Kesemua oksida mempunyai ikatan kovalen.

B Oksida dengan keadaan pengoksidaan +4 boleh bertindak balas dengan alkali.

C Oksida dengan keadaan pengoksidaan +4 lebih stabil apabila menuruni kumpulan.

D Keasidan oksida dengan keadaan pengoksidaan +2 bertambah apabila menuruni kumpulan.

12 Satu larutan akueus X, suatu campuran dua sebatian, mempunyai sifat-sifat yang berikut.

(i) Terurai dalam kehadiran cahaya untuk membentuk gas.

(ii) Bertindak balas dengan akueus barium hidroksida untuk membentuk garam dan air.

(iii) Bertindak balas dengan akueus argentum nitrat untuk membentuk mendakan yang

melarut dalam ammonia akueus.

Sebatian yang berikut mungkin terdapat dalam larutan akueus X.

I HCl

II HBr

III HOCl

IV NH4Cl

Apakah X ?

A I dan II

B I dan III

C II dan IV

D III dan IV

13 Halogen atau sebatiannya tidak digunakan

A sebagai detergen

B dalam fotografi

C sebagai propelan dalam aerosol

D dalam pensterilan air

962/2

- 26 -


14 In which compound does the transition element have the lowest oxidation state?

A NH4VO3

B K3Fe(CN)6

C CrO2Cl2

D MnC2O4

15 A transition element can act as a homogeneous catalyst because

A it exhibits variable oxidation states

B it decreases the enthalpy of reactions

C it supplies energy to increase the rate of effective collisions

D it supplies electrons to facilitate adsorption through the formation of temporary bonds

962/2

- 27 -


14 Sebatian yang manakah unsur peralihannya mempunyai keadaan pengoksidaan paling rendah?

A NH4VO3

B K3Fe(CN)6

C CrO2Cl2

D MnC2O4

15 Unsur peralihan boleh bertindak sebagai mangkin homogen kerana

A unsur peralihan mempamerkan keadaan pengoksidaan yang berubah

B unsur peralihan mengurangkan entalpi tindak balas

C unsur peralihan membekalkan tenaga untuk menambah kadar perlanggaran efektif

D unsur peralihan membekalkan elektron untuk memudahkan penjerapan melalui pembentukan

ikatan sementara.

962/2

- 28 -




16 (a) The two common oxides of lead are lead(II) oxide and lead(IV) oxide. Lead(II) oxide

dissolves readily in aqueous nitric acid. Lead(IV) oxide reacts with concentrated hydrochloric acid to

form lead(II) chloride and chlorine.

(i) Write a balanced equation for the reaction between lead(II) oxide and aqueous nitric

acid. [1 mark]

....................................................................................................................................................................

(ii) What is the property shown by lead(II) oxide in the reaction in part (i)? [1 mark]

....................................................................................................................................................................

(iii) Write a balanced equation for the reaction between lead(IV) oxide and concentrated

hydrochloric acid. [1 mark]

....................................................................................................................................................................

(iv) State the change in the oxidation number of lead in the reaction in part (iii). [1 mark]

....................................................................................................................................................................

(v) What is the property shown by lead(IV) oxide in this reaction? [1 mark]

...................................................................................................................................................................

(vi) State the relative stability of lead(II) and lead(IV) compounds. [1 mark]

...................................................................................................................................................................

(b) PbCl4 is a liquid at room temperature and undergoes hydrolysis.

(i) State the geometrical shape of PbCl4. [1 mark]

....................................................................................................................................................................

(ii) Why does PbCl4 undergo hydrolysis? [1 mark]

....................................................................................................................................................................

962/2

- 29 -




16 (a) Dua oksida plumbum yang lazim ialah plumbum(II) oksida dan plumbum(IV) oksida.

Plumbum(II) oksida melarut dengan mudah dalam asid nitrik akueus. Plumbum(IV) oksida bertindak

balas dengan asid hidroklorik pekat untuk membentuk plumbum(II) klorida dan klorin.

(i) Tulis persamaan berimbang bagi tindak balas antara plumbum(II) oksida dengan asid

nitrik akueus. [1 markah]

....................................................................................................................................................................

(ii) Apakah sifat yang ditunjukkan oleh plumbum(II) oksida dalam tindak balas pada

bahagian (i)? [1 markah]

....................................................................................................................................................................

(iii) Tulis persamaan berimbang bagi tindak balas antara plumbum(IV) oksida dengan asid

hdroklorik pekat. [1 markah]

....................................................................................................................................................................

(iv) Nyatakan perubahan nombor pengoksidaan plumbum dalam tindak balas pada bahagian

(iii). [1 markah]

....................................................................................................................................................................

(v) Apakah sifat yang ditunjukkan oleh plumbum(IV) oksida dalam tindak balas ini?

[1 markah]

...................................................................................................................................................................

(vi) Nyatakan kestabilan relatif sebatian plumbum(II) dan sebatian plumbum(IV).

[1 markah]

...................................................................................................................................................................

(b) PbCl4 adalah cecair pada suhu bilik dan mengalami hidrolisis.

(i) Nyatakan bentuk geometri PbCl4. [1 markah]

....................................................................................................................................................................

(ii) Mengapakah PbCl4 mengalami hidrolisis? [1 markah]

....................................................................................................................................................................

962/2

Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-pu

tus

ini.

- 30 -


17 (a) A bleach liquid can be prepared from the reaction of chlorine with aqueous solution of

sodium hydroxide at room temperature.

(i) Write a balanced ionic equation for the reaction that occurs. [1 mark]

....................................................................................................................................................................

(ii) State the change in oxidation state of chlorine in the reaction. [1 mark]

....................................................................................................................................................................

(iii) State the active substance of bleaching liquid formed. [1 mark]

....................................................................................................................................................................

(b) Photochromic glass is made based on the concept of black-white photography.

(i) What is the additive substance of photochromic glass? [1 mark]

....................................................................................................................................................................

(ii) State what happens when photochromic glass is exposed to light, and write a balanced

equation for the reaction. [3 marks]

....................................................................................................................................................................

....................................................................................................................................................................

Equation:....................................................................................................................................................

962/2

- 31 -


17 (a) Satu cecair peluntur boleh disediakan daripada tindak balas klorin dengan larutan akueus

natrium hidroksida pada suhu bilik.

(i) Tulis persamaan berimbang bagi tindak balas yang berlaku. [1 markah]

....................................................................................................................................................................

(ii) Nyatakan perubahan keadaan pengoksidaan klorin dalam tindak balas itu. [1 markah]

....................................................................................................................................................................

(iii) Nyatakan bahan aktif cecair peluntur yang terbentuk. [1 markah]

....................................................................................................................................................................

(b) Kaca fotokromik dibuat berdasarkan konsep fotografi hitam putih.

(i) Apakah bahan tambahan kaca fotokromik? [1 markah]

....................................................................................................................................................................

(ii) Nyatakan apakah yang berlaku apabila kaca fotokromik terdedah kepada cahaya, dan

tulis persamaan berimbang bagi tindak balas itu. [3 markah]

....................................................................................................................................................................

....................................................................................................................................................................

Persamaan:................................................................................................................................................

962/2

Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-pu

tus

ini.

- 32 -




18 (a) Liquid hydrazine, N2H4, is used as a rocket fuel because its enthalpy of combustion is highly

exothermic. The thermochemical equation for the combustion of hydrazine is as follows:

N2H4(1) + O2(g) N2(g) + 2H2O(g) H = –534.0 kJ

(i) In an experiment, 1.0 g of hydrazine is burnt in a bomb calorimeter. Calculate the

temperature change if the total heat capacity of the bomb calorimeter and its contents is 5.86 kJ C–1

.

[5 marks]

(ii) The enthalpy of formation of water vapour is –242.0 kJ mol–1

. Calculate the enthalpy

of formation of hydrazine. [3 marks]

(b) The enthalpies of vaporisation of the sodium, aluminium and chlorine are given in the table

below.

Element Enthalpy of vaporisation/kJ mol–1

Sodium 103

Aluminium 294

Chlorine 20.4

(i) Explain the variations in the enthalpies of vaporisation of sodium, aluminium and

chlorine. [4 marks]

(ii) Sodium and aluminium react separately with chlorine to form sodium chloride and

aluminium chloride respectively. Which of these compounds has a higher enthalpy of vaporisation?

Justify your answer. [3 marks]

19 Explain the variations of the following properties on descending Group 2 of the Periodic Table.

Write equations where appropriate.

(a) First ionisation energy of the elements. [5 marks]

(b) Reactivity of the elements towards water. [5 marks]

(c) Thermal stability of their nitrates. [5 marks]

962/2

- 33 -




18 (a) Cecair hidrazina, N2H4, digunakan sebagai bahan api roket kerana entalpi pembakarannya

sangat eksotermik. Persamaan termokimia bagi pembakaran hidrazina adalah seperti yang berikut:

N2H4(c) + O2(g) N2(g) + 2H2O(g) H = –534.0 kJ

(i) Dalam satu uji kaji, 1.0 g hidrazina dibakar dalam kalorimeter bom. Hitung perubahan

suhu jika jumlah muatan haba kalorimeter bom dan kandungannya itu ialah 5.86 kJ C–1

.

[5 markah]

(ii) Entalpi pembentukan wap air ialah –242.0 kJ mol–1

. Hitung entalpi pembentukan

hidrazina. [3 markah]

(b) Entalpi pengewapan natrium, aluminium, dan klorin diberikan dalam jadual di bawah.

Unsur Entalpi pengewapan /kJ mol–1

Natrium 103

Aluminium 294

Klorin 20.4

(i) Jelaskan perubahan entalpi pengewapan natrium, aluminium, dan klorin. [4 markah]

(ii) Natrium dan aluminium masing-masing bertindak balas secara berasingan dengan

klorin untuk membentuk natrium klorida dan aluminium klorida. Sebatian tersebut yang manakah

yang mempunyai entalpi pegewapan paling tinggi? Justifikasikan jawapan anda. [3 markah]

19 Jelaskan ubahan sifat yang berikut apabila menuruni Kumpulan 2 Jadual Berkala. Tulis

persamaan di mana-mana yang sesuai.

(a) Tenaga pengionan pertama unsur. [5 markah]

(b) Kereaktifan unsur terhadap air. [5 markah]

(c) Kestabilan terma nitratnya. [5 markah]

962/2

- 34 -


20 (a) The common oxidation states of the transition metal ions below are +2 and +3. The graph

below shows the trend in standard reduction potentials of M 3+

(aq)/M 2+

(aq) system of selected

transition metal ions.

(i) Name two ions that have stable +2 oxidation state in aqueous solution. Justify your

answer. [3 marks]

(ii) The standard reduction potentials, E , of several species are given below.

Reaction E /V

Fe2+

+ 2e Fe 0.44

Fe3+

+ 3e Fe 0.04

Fe3+

+ 3e Fe2+

+1.77

O2 + 4H+ + 4e 2H2O +1.23

O2 + 2H2O + 4e 4OH +0.40

O2 + 2H+ + 2e H2O2 +0.68

Using the appropriate E values, explain why an aqueous solution of iron(II) ions changes

from pale green to yellow when exposed to air. [6 marks]

(b) (i) Name the complex ions [Ni(NH2CH2CH2NH2)3]2+

and [Ni(CN)4]2

according to IUPAC

nomenclature. [2 marks]

(ii) Aqueous nickel(II) chloride reacts with aqueous ammonia to form a precipitate X. X

dissolves in excess aqueous ammonia to form a solution Y. Write the equations for the reactions that

occur, and state the colours of X and Y. [4 marks]

962/2

Standard

electrode

potential

/V

- 35 -


20 (a) Keadaan pengoksidaan lazim bagi ion logam peralihan di bawah ialah +2 dan +3. Graf

di bawah menunjukkan trend keupayaan penurunan piawai bagi sistem M 3+

(ak)/M 2+

(ak) bagi ion

logam peralihan yang terpilih.

(i) Namakan dua ion yang mempunyai keadaan pengoksidaan +2 yang stabil dalam larutan

akueus. Justifikasikan jawapan anda. [3 markah]

(ii) Keupayaan penurunan piawai, E , bagi beberapa spesis diberikan di bawah.

Tindak balas E /V

Fe2+

+ 2e Fe 0.44

Fe3+

+ 3e Fe 0.04

Fe3+

+ 3e Fe2+

+1.77

O2 + 4H+ + 4e 2H2O +1.23

O2 + 2H2O + 4e 4OH +0.40

O2 + 2H+ + 2e H2O2 +0.68

Dengan menggunakan nilai E yang bersesuaian, jelaskan mengapa larutan akueus ion

ferum(II) berubah daripada hijau pucat kepada kuning apabila terdedah ke udara. [6 markah]

(b) (i) Namakan ion kompleks [Ni(NH2CH2CH2NH2)3]2+

dan ion kompleks [Ni(CN)4]2

mengikut tatanama IUPAC. [2 markah]

(ii) Nikel(II) klorida akueus bertindak balas dengan ammonia akueus untuk membentuk

mendakan X. X melarut dalam ammonia akueus berlebihan untuk membentuk larutan Y. Tulis

persamaan bagi tindak balas yang berlaku, dan nyatakan warna X dan Y. [4 markah]

962/2

Keupayaan

elektrod

piawai

/V

- 36 -




SPECIMEN PAPER

962/3 STPM

CHEMISTRY (KIMIA)

PAPER 3 (KERTAS 3)







STPM 962/3


(Untuk kegunaan

pemeriksa)

Section B

(Bahagian B)

16

17

Section C

(Bahagian C)

Total

(Jumlah)



TOLD TO DO SO.

There are fifteen questions in Section A. For each question, four choices of answers are given. Choose one correct answer and indicate it on the

Multiple-choice Answer Sheet provided. Read the instructions on the Multiple-choice Answer Sheet very carefully. Answer all questions. Marks

will not be deducted for wrong answers.

Answer all questions in Section B. Write your answers in the spaces provided.

Answer any two questions in Section C. All essential working should be shown. For numerical answers, unit should be quoted wherever appropriate.

Begin each answer on a fresh sheet of paper and arrange your answers in

numerical order.

Tear off the front page of this question paper and your answer sheets of

Section B, and tie both of them together with your answer sheets of Section C.


Ple

ase

tea

r off

alo

ng t

he

per

fora

ted l

ine.

(Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-putu

s in

i.)



DEMIKIAN.

Ada lima belas soalan dalam Bahagian A. Bagi setiap soalan, empat pilihan jawapan diberikan.

Pilih satu jawapan yang betul dan tandakan jawapan itu pada Borang Jawapan Aneka Pilihan yang dibekalkan. Baca arahan pada Borang Jawapan Aneka Pilihan itu dengan teliti. Jawab semua soalan.

Markah tidak akan ditolak bagi jawapan yang salah. Jawab semua soalan dalam Bahagian B. Tulis jawapan anda di ruang yang disediakan.

Jawab mana-mana dua soalan dalam Bahagian C. Semua jalan kerja yang sesuai hendaklah

ditunjukkan. Bagi jawapan berangka, unit hendaklah dinyatakan di mana-mana yang sesuai. Mulakan setiap jawapan pada helaian kertas jawapan yang baharu dan susun jawapan anda mengikut tertib

berangka.

Koyakkan muka hadapan kertas soalan ini dan helaian jawapan anda bagi Bahagian B, dan ikatkan kedua-duanya bersama-sama dengan helaian jawapan anda bagi Bahagian C.


- 37 -




1 Which compound has a carbon atom that exhibits sp3 hybridisation?

A CH2=CH CH=CH2

B

C

D H C C H

2 When 0.1 mol of hydrocarbon X is burnt in excess oxygen, 17.6 g carbon dioxide is produced.

0.1 mol of X is found to react with 4.48 dm3 of bromine vapour under standard conditions. What is

the possible structural formula of X ?

[Relative atomic massess of C and O are 12.0 and 16.0 respectively ; the molar volume of a gas is

22.4 dm3 at stp.]

A CH3CH=CHCH3

B CH2=C=C=CH2

C CH3CH2CH2CH3

D CH2=CHCH=CH2

3 Which compound shows optical isomerism?

A CH3CH=CHCH3

B CH3CH2C(Cl)2CH3

C CH3CH2CH(OH)CH3

D HOCH2CH(OH)CH2OH

4 Which reaction involves an electrophilic reagent?

A CH3CH3 + Cl2 CH3CH2Cl + HCl

B CH3Br + NaOH CH3OH + NaBr

C CH3CH=CH2 + HBr CH3CHBrCH3

D CH3COOH + CH3CH2OH CH3COOCH2CH3 + H2O

5 A mixture of excess ethane and chlorine is exposed to light. What is the major product of the

reaction?

A Cl3CCH3

B ClCH2CH3

C Cl2CHCH3

D Cl2CHCHCl2

962/3

CH=CH2

CH3

- 38 -




1 Sebatian yang manakah yang mempunyai atom karbon yang menunjukkan penghibridan sp3?

A CH2=CH CH=CH2

B

C

D H C C H

2 Apabila 0.1 mol hidrokarbon X dibakar dalam oksigen berlebihan, 17.6 g karbon dioksida

dihasilkan. Didapati bahawa 0.1 mol X akan bertindak balas dengan 4.48 dm3 wap bromin dalam

keadaan piawai. Apakah formula struktur yang mungkin bagi X ?

[Jisim atom relatif bagi C dan O masing-masing ialah 12.0 dan 16.0; isi padu molar gas ialah

22.4 dm3 pada stp.]

A CH3CH=CHCH3

B CH2=C=C=CH2

C CH3CH2CH2CH3

D CH2=CHCH=CH2

3 Sebatian yang manakah yang menunjukkan isomer optik?

A CH3CH=CHCH3

B CH3CH2C(Cl)2CH3

C CH3CH2CH(OH)CH3

D HOCH2CH(OH)CH2OH

4 Tindak balas yang manakah yang melibatkan reagen elektrofilik?

A CH3CH3 + Cl2 CH3CH2Cl + HCl

B CH3Br + NaOH CH3OH + NaBr

C CH3CH=CH2 + HBr CH3CHBrCH3

D CH3COOH + CH3CH2OH CH3COOCH2CH3 + H2O

5 Satu campuran etana yang berlebihan dan klorin terdedah kepada cahaya. Apakah hasil utama

tindak balas itu?

A Cl3CCH3

B ClCH2CH3

C Cl2CHCH3

D Cl2CHCHCl2

962/3

CH=CH2

CH3

- 39 -


6 An organic compound Z undergoes a catalytic hydrogenation reaction. Z also reacts with

hydrogen bromide to form 2-bromopropane.

The structural formula of Z is

A CH3CH2CH3

B CH2 CH2

C CH3CH CH2

D CH3CH(OH)CH3

7 The following statements are about nitration of benzene.

I Nitric acid acts as an electrophile.

II The reaction involves free radicals.

III Nitronium ion, NO2+, is an electrophile.

IV Nitronium ion, NO2+, is formed from concentrated H2SO4 and HNO3.

Which statements regarding the mechanism of nitration of benzene are true?

A I and II

B I and IV

C II and III

D III and IV

8 Which reaction occurs through SN1 mechanism?

A C6H5CH2Br + NH3 C6H5CH2NH2 + HBr

B (CH3)3CBr + NaOH (CH3)3COH + NaBr

C CH3CHBrCH3 + KCN CH3CH(CN)CH3 + KBr

D CH3CH2CH2Br + KOH CH3CH2CH2OH + KBr

9 When an optically active compound Z is heated with chromic acid, the product formed is not

optically active but react with alkaline iodine. Compound Z could be

A (CH3)2CHCH2OH

B CH3CH2CH(OH)CH2CH3

C CH3CH2CH2CH(OH)CH3

D CH(OH)CH2CH3

10 Compound X is oxidised to compound Y. Y does not reduce Fehling‟s solution. X could be

A CH3CH2CH2OH

B CH3CHOHCH3

C (CH3)3COH

D CH3COCH3

962/3

- 40 -


6 Satu sebatian organik Z mengalami tindak balas penghidrogenan bermangkin. Z juga bertindak

balas dengan hidrogen bromida untuk membentuk 2-bromopropana.

Formula struktur Z ialah

A CH3CH2CH3

B CH2 CH2

C CH3CH CH2

D CH3CH(OH)CH3

7 Penyataan yang berikut adalah tentang penitratan benzena.

I Asid nitrik bertindak sebagai elektrofil.

II Tindak balas melibatkan radikal bebas.

III Ion nitronium, NO2+ ialah elektrofil.

IV Ion nitronium, NO2+, terbentuk daripada H2SO4 pekat dan HNO3.

Penyataan yang manakah yang betul berkaitan dengan mekanisme penitratan benzena?

A I dan II

B I dan IV

C II dan III

D III dan IV

8 Tindak balas yang manakah yang berlaku melalui mekanisme SN1?

A C6H5CH2Br + NH3 C6H5CH2NH2 + HBr

B (CH3)3CBr + NaOH (CH3)3COH + NaBr

C CH3CHBrCH3 + KCN CH3CH(CN)CH3 + KBr

D CH3CH2CH2Br + KOH CH3CH2CH2OH + KBr

9 Apabila sebatian Z yang aktif optik dipanaskan dengan asid kromik, hasil yang terbentuk tidak

aktif optik tetapi bertindak balas dengan iodin beralkali. Sebatian Z mungkin

A (CH3)2CHCH2OH

B CH3CH2CH(OH)CH2CH3

C CH3CH2CH2CH(OH)CH3

D CH(OH)CH2CH3

10 Sebatian X dioksidakan kepada sebatian Y. Y tidak menurunkan larutan Fehling‟s. X mungkin

A CH3CH2CH2OH

B CH3CHOHCH3

C (CH3)3COH

D CH3COCH3

962/3

- 41 -


11 Which compound produces a yellow precipitate when reacts with 2,4-dinitrophenylhydrazine?

A CH3CH2CH2C OH

B CH3CH2C OCH3

C CH3CH2CH2C Cl

D CH3CH2CCH3

12 Phenol is used to prepare CH3COOC6H5 through an intermediate X as shown in the following

scheme.

C6H5OH X CH3COOC6H5

What are reagent I and reagent II in the above scheme?

Reagent I Reagent II

A Na CH3COCl

B PCl5 CH3COCl

C PCl5 CH3COOH

D NaOH CH3COOH

13 An amine is produced in a two-step reaction as shown below.

2-Bromopropane Amine

What is the structural formula of this amine?

A CH3CH2CH2CH2NH2

B CH3CH2CH(CH3)NH2

C (CH3)2CHCH2NH2

D CH3CH(NH2)CH3

14 The structural formula of a peptide is as follows.

The peptide is

A a dipeptide

B a tripeptide

C a neutral compound

D an acidic compound

962/3

KCN/ethanol Na/ethanol

Reagent I Reagent II

H2N CH

CH2OH

C OH N

H CH3

CH C N

H

CH C

CH2CH2CH2NH2

O O O

O

O

O

O

- 42 -


11 Sebatian yang manakah yang menghasilkan mendakan kuning apabila bertindak balas dengan

2,4-dinitrofenilhidrazina?

A CH3CH2CH2C OH

B CH3CH2C OCH3

C CH3CH2CH2C Cl

D CH3CH2CCH3

12 Fenol digunakan untuk menyediakan CH3COOC6H5 melalui perantaraan X seperti ditunjukkan

dalam skema yang berikut.

C6H5OH X CH3COOC6H5

Apakah reagen I dan reagen II dalam skema di atas?

Reagen I Reagen II

A Na CH3COCl

B PCl5 CH3COCl

C PCl5 CH3COOH

D NaOH CH3COOH

13 Suatu amina dihasilkan dalam dua langkah tindak balas seperti ditunjukkan di bawah.

2-Bromopropana Amina

Apakah formula struktur amina ini?

A CH3CH2CH2CH2NH2

B CH3CH2CH(CH3)NH2

C (CH3)2CHCH2NH2

D CH3CH(NH2)CH3

14 Formula struktur suatu peptida adalah seperti yang berikut.

Peptida itu ialah

A dipeptida

B tripeptida

C sebatian neutral

D sebatian berasid

962/3

KCN/etanol Na/etanol

Reagen I Reagen II

O

O

O

O

H2N CH

CH2OH

C OH N

H CH3

CH C N

H

CH C

CH2CH2CH2NH2

O O O

- 43 -


15 The following is a pair of a polymer and its possible repeating unit.

Polymer Repeating unit

I Poly(propene) CH(CH3)CH2

II Poly(styrene) CHCH2CHCH2

III Terylene OCH2CH2OCO

IV Nylon-6,6 CO(CH2)5NH

Which is the correct match between a polymer and its repeating unit?

A I and II

B I and IV

C II and III

D III and IV

962/3

CO

- 44 -


15 Padanan yang berikut adalah tentang polimer dan unit ulangan yang mungkin.

Polimer Unit ulangan

I Poli(propena) CH(CH3)CH2

II Poli(stirena) CHCH2CHCH2

III Terilena OCH2CH2OCO

IV Nilon-6,6 CO(CH2)5NH

Padanan yang manakah yang betul antara polimer dan unit ulangannya?

A I dan II

B I dan IV

C II dan III

D III dan IV

962/3

CO

- 45 -




16 (a) Starting with 1-bromopropane, CH3CH2CH2Br, show the reaction schemes to synthesise the

following carboxylic acids. [4 marks]

(i) CH3CH2COOH

(ii) CH3CH2CH2COOH

(b) Write equations for the reactions between benzoyl chloride, C6H5COCl, and the following

compounds, and name the organic products according to the IUPAC nomenclature. [4 marks]

(i) CH3NH2

(ii) C6H5OH

962/3

- 46 -




16 (a) Bermula dengan 1-bromopropana, CH3CH2CH2Br, tunjukkan skema tindak balas untuk

mensintesiskan asid karboksilik yang berikut. [4 markah]

(i) CH3CH2COOH

(ii) CH3CH2CH2COOH

(b) Tulis persamaan bagi tindak balas antara benzoil klorida, C6H5COCl, dengan sebatian yang

berikut, dan namakan hasil-hasil organik itu mengikut tatanama IUPAC. [4 markah]

(i) CH3NH2

(ii) C6H5OH

962/3

Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-pu

tus

ini.

- 47 -


17 (a) Compound X is a phenylalanine which is an essential amino acid that must be provided in the

diet for healthy growth. The structural formula of X is given below.

(i) Name the functional groups in compound X. [2 marks]

....................................................................................................................................................................

....................................................................................................................................................................

(ii) Draw the structure of X at isoelectric point. State the direction of the movement of X

when a potential difference is applied to an aqueous solution of X at isoelectric point. [2 marks]

(iii) Draw the structure of X at pH = 2. [1 mark]

(iv) Draw the structure of dipeptide formed from two molecules of X. [1 mark]

(v) Name the lingkage in the dipeptide. [1 mark]

....................................................................................................................................................................

962/3

CH2 CHCOOH

NH2

- 48 -


17 (a) Sebatian X ialah fenilalanina yang merupakan asid amino perlu disediakan dalam diet untuk

pertumbuhan yang sihat. Formula struktur X diberikan di bawah.

(i) Namakan kumpulan berfungsi dalam sebatian X. [2 markah]

....................................................................................................................................................................

....................................................................................................................................................................

(ii) Lukis struktur X pada takat isoelektrik. Nyatakan arah gerakan X apabila satu beza

keupayaan dikenakan pada larutan akueus X pada takat isoelektrik. [2 markah]

(iii) Lukis struktur X pada pH = 2. [1 markah]

(iv) Lukis struktur dipeptida yang terbentuk daripada dua molekul X. [1 markah]

(v) Namakan rangkaian dalam dipeptida itu. [1 markah]

....................................................................................................................................................................

962/3

CH2 CHCOOH

NH2

Sil

a k

oya

kkan d

i se

panja

ng g

ari

s putu

s-pu

tus

ini.

- 49 -




18 (a) Methylbenzene is obtained from benzene using Friedel-Crafts reaction.

(i) State the reagent and conditions required for the reaction. [2 marks]

(ii) Write a balanced equation for the reaction. [1 mark]

(iii) State the electrophile involved in this reaction. [1 mark]

(iv) Describe a simple chemical test to detect the presence of methylbenzene. Write an

equation for the reaction involved. [3 marks]

(b) Chlorine gas is bubbled into methylbenzene in the presence of light and in the absence of a

catalyst.

(i) Draw structural formulae of any two organic compounds formed and name them.

[4 marks]

(ii) Write the mechanism for the reaction. [4 marks]

19 The table below lists the acid dissociation constants, Ka, for three hydroxy compounds in aqueous

solutions at 298 K.

Name of compound Formula Ka/mol dm3

Cyclohexanol 1.0 1018

Phenol 1.0 1010

4-Methylphenol 6.8 1011

(a) Arrange the three compounds above in the order of increasing acidity. Justify your answer.

[7 marks]

(b) Describe a chemical test to differentiate the acidity between cyclohexanol and phenol.

[4 marks]

(c) State the reagents and reaction conditions in the oxidation and bromination of

4-methylphenol, and draw the structural formula of the products formed. [4 marks]

962/3

OH

OH

H3C OH

- 50 -




18 (a) Metilbenzena diperoleh daripada benzena menggunakan tindak balas Friedel-Crafts.

(i) Nyatakan reagen dan keadaan yang diperlukan bagi tindak balas itu. [2 markah]

(ii) Tulis persamaan berimbang bagi tindak balas itu. [1 markah]

(iii) Nyatakan elektrofil yang terlibat dalam tindak balas tersebut. [1 markah]

(iv) Perihalkan satu ujian kimia ringkas untuk mengesan kehadiran metilbenzena. Tulis

persamaan bagi tindak balas yang terlibat. [3 markah]

(b) Gas klorin dilalugelembungkan ke dalam metilbenzena dalam kehadiran cahaya dan dalam

ketakhadiran mangkin.

(i) Lukis formula struktur mana-mana dua sebatian organik yang terbentuk dan

namakannya. [4 markah]

(ii) Tulis mekanisme bagi tindak balas itu. [4 markah]

19 Jadual di bawah menyenaraikan pemalar penceraian asid, Ka, bagi tiga sebatian hidroksi dalam

larutan akueus pada 298 K.

Nama sebatian Formula Ka/mol dm3

Sikloheksanol 1.0 1018

Fenol 1.0 1010

4-Metilfenol 6.8 1011

(a) Susun tiga sebatian di atas mengikut tertib menaik keasidannya. Justifikasikan jawapan anda.

[7 markah]

(b) Perihalkan satu ujian kimia untuk membezakan keasidan antara sikloheksanol dengan fenol.

[4 markah]

(c) Nyatakan reagen dan keadaan tindak balas dalam pengoksidaan dan pembrominan

4-metilfenol, dan lukis formula struktur hasil yang terbentuk. [4 markah]

962/3

OH

OH

H3C OH

- 51 -


20 A monobasic carboxylic acid Z has the following composition by mass: carbon, 54.5%; hydrogen,

9.1%; and oxygen, 36.4%. Titration of 0.10 g of Z requires 11.40 cm3 of 0.100 mol dm

3 sodium

hyroxide for complete neutralisation. Z can be synthesised from -propanol by a three-step reaction as

shown below.

CH3CH2CH2OH X Y Z

(a) Determine the empirical and molecular formulae of Z. [6 marks]

(b) State the reagents and the conditions required in each of the steps. [3 marks]

(c) Draw the structural formulae of X, Y and Z. [3 marks]

(d) A mixture of -propanol and Z is refluxed with concentrated sulphuric acid. Name the

reaction and the organic product formed, and write a balanced equation for the reaction involved.

[3 marks]

[Relative atomic masses of H, C and O are 1.0, 12.0 and 16.0 respectively.]

962/3

I II III

1

1

- 52 -


20 Satu asid karboksilik monobes Z mempunyai komposisi mengikut jisim: karbon, 54.5%; hidrogen,

9.1%; dan oxigen, 36.4%. Pentitratan 0.10 g Z memerlukan 11.40 cm3 natrium hidroksida

0.100 mol dm3 untuk peneutralan lengkap. Z dapat disintesiskan daripada -propanol melalui tiga

langkah tindak balas seperti ditunjukkan di bawah.

CH3CH2CH2OH X Y Z

(a) Tentukan formula empirik dan formula molekul Z. [6 markah]

(b) Nyatakan reagen dan keadaan yang diperlukan dalam setiap langkah itu. [3 markah]

(c) Lukis formula struktur X, Y, dan Z. [3 markah]

(d) Satu campuran -propanol dan Z direfluks dengan asid sulfurik pekat. Namakan tindak balas

dan hasil organik yang terbentuk, dan tulis persamaan berimbang bagi tindak balas yang terlibat.

[3 markah]

[Jisim atom relatif bagi H, C, dan O masing-masing ialah 1.0, 12.0, dan 16.0.]

962/3

I II III

1

1

- 53 -


SPECIMEN EXPERIMENT

962/4 STPM

CHEMISTRY

PAPER 4




STPM 962/4

- 54 -


STPM CHEMISTRY STUDENT’S MANUAL 20___/20___

Topic : Thermochemistry

Purpose : To determine the heat of neutralisation of a strong acid with a strong base

Materials : KA 1 is 1.0 mol dm-3

hydrochloric acid.

KA 2 is a 1.0 mol dm-3

solution of a strong acid W.

KA 3 is 1.0 mol dm-3

aqueous sodium hydroxide.


nitric acid.


aqueous potassium hydroxide.

Procedure : (a) By means of a pipette, place 10.0 cm3 of KA 1 into a plastic cup. Record the

temperature of KA 1 as the initial temperature of mixture X in the table below.

By means of a measuring cylinder, add 30 cm3 of solution KA 3 into the plastic

cup containing KA 1. Stir mixture X carefully with a thermometer and record the

highest temperature attained in the table below. Pour away mixture X from the

plastic cup. Then clean and rinse the cup with distilled water.

Repeat the above procedure using

(i) 10.0 cm3 of KA 2 to replace KA 1 to obtain mixture Y, and

(ii) 10.0 cm3 of KA 4 and 30 cm

3 of KA 5 to replace KA 1 and KA 3

respectively to obtain mixture Z.

Results : (b) Complete the table below.

Mixture X

KA 1 + KA 3

Mixture Y

KA 2 + KA 3

Mixture Z

KA 4 + KA 5

Highest temperature/ C

Initial temperature/ C

Increase in temperature/ C

Questions : (c) If 4.2 Joules is required to raise the temperature by 1 C for 1 cm3 of solution,

calculate the heat released for each of the experiments conducted.

(d) Calculate the number of moles of the following solutions added into the plastic

cup.

(i) Sodium hydroxide

(ii) Potassium hydroxide

(iii) Hydrochloric acid

(iv) Nitric acid

(v) Acid W

962/4

- 55 -


STPM CHEMISTRY STUDENT’S MANUAL 20___/20___

(e) Write an ionic equation for the reaction taking place in mixtures X, Y, and Z.

(f) Calculate the heat of neutralisation for each reaction.

(g) (i) Explain why the values of the heat of neutralisation you obtained differ in

mixtures X, Y, and Z.

(ii) The heat of neutralisation between a strong acid and a strong base is

57.3 kJ mol1. How would you improve the given procedure so that an

approximate value of 57.3 kJ mol1 could be obtained?

962/4

- 56 -




SPECIMEN PAPER

962/5 STPM

CHEMISTRY (KIMIA)

PAPER 5 (KERTAS 5)







STPM 962/5


(Untuk kegunaan

pemeriksa)

1

2

3

Total

(Jumlah)



TOLD TO DO SO.

Answer all questions. Write your answers in the spaces provided.


All working should be shown. Numerical answers should be given to

an appropriate number of significant figures or decimal places; units

should be quoted where appropriate.

For your calculations, use the following relative atomic masses:

H = 1.0; Mn = 54.9; N = 14.0; C = 12.0; O = 16.0; K = 39.1.



DEMIKIAN.

Jawab semua soalan. Tulis jawapan anda dalam ruang yang disediakan.


Semua kerja hendaklah ditunjukkan. Jawapan berangka hendaklah diberikan hingga bilangan

anga bererti atau tempat perpuluhan yang sesuai; unit hendaklah dinyatakan di mana-mana yang

sesuai.

Untuk penghitungan anda, gunakan jisim atom relatif yang berikut:

H = 1.0; Mn = 54.9; N = 14.0; C = 12.0; O = 16.0; K = 39.1.

- 57 -


1 An experiment was carried out to determine the percentage of ammonium ethanedioate,

(NH4)2C2O4, in a mixture of two ethanedioate salts.

An aqueous solution of X was prepared by dissolving a mixture of (NH4)2C2O4 and KHC2O4 in

distilled water.

(a) In this experiment, 25.0 cm3 of the aqueous solution of X was pipetted into a titration flask

followed by 25 cm3 of sulphuric acid and then heated to a temperature of approximately 60

oC. The

aqueous solution of X was then titrated with 0.02 mol dm3 aqueous solution of potassium

manganate(VII) . The reactions involved are shown by the following equation.

2MnO4 (aq) + 5C2O42

(aq) + 16H+(aq) 2Mn

2+(aq) + 10CO2

(g) + 8H2O(l)

(i) State the steps taken in transferring 25.0 cm3 of the aqueous solution of X into the

titration flask by using a pipette. [3 marks]

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

(ii) The burette readings for the rough and accurate titrations are shown in the table below.

Complete the table. [1 mark]

Titration Rough Accurate

First Second Third

Final reading/cm3 30.0 30.75 30.05 30.90

Initial reading/cm3 1.1 2.20 1.30 2.20

Volume of KMnO4

aqueous solution/cm3

28.9

(iii) By showing the suitable values of titres chosen, calculate the average titre value.

[2 marks]

962/5

- 58 -


1 Satu uji kaji telah dijalankan untuk menentukan peratusan ammonium etanadioat, (NH4)2C2O4,

dalam satu campuran dua garam etanadioat.

Larutan akueus X disediakan dengan melarutkan campuran (NH4)2C2O4 dan KHC2O4 dalam air

suling.

(a) Dalam uji kaji ini, 25.0 cm3 larutan akueus X dipipetkan ke dalam kelalang pentitratan diikuti

25 cm3 asid sulfurik dan kemudian dipanaskan ke suhu lebih kurang 60 °C. Larutan akues X kemudian

dititratkan dengan larutan akues kalium manganat(VII) 0.02 mol dm3. Tindak balas yang terlibat

ditunjukkan dengan persamaan yang berikut.

2MnO4 (ak) + 5C2O42

(ak) + 16H+(ak) 2Mn

2+(ak) + 10CO2

(g) + 8H2O(c)

(i) Nyatakan langkah-langkah yang diambil untuk memindahkan 25.0 cm3 larutan akueus

X ke dalam kelalang pentitratan dengan menggunakan sebuah pipet. [3 markah]

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

……………………………………………………………………………………………………………

(ii) Bacaan buret bagi pentitratan kasar dan jitu ditunjukkan dalam jadual di bawah.

Lengkapkan jadual ini. [1 markah]

Pentitratan Kasar Jitu

Pertama Kedua Ketiga

Bacaan akhir/cm3 30.0 30.75 30.05 30.90

Bacaan awal/cm3 1.1 2.20 1.30 2.20

Isi padu larutan akueus

KMnO4 /cm3

28.9

(iii) Hitung nilai purata titer dengan menunjukkan nilai-nilai titer yang sesuai digunakan.

[2 markah]

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- 59 -


(iv) Calculate the concentration, in mol dm3, of ethanedioate ions C2O4

2 in the aqueous

solution of X. [2 marks]

(v) Name a suitable apparatus used to measure 25 cm3 of sulphuric acid. [1 mark]

……………………………………………………………………………………………………………

(b) When 25.0 cm3 of the aqueous solution of X was titrated with 0.05 mol dm

3 aqueous solution

of sodium hydroxide using a suitable indicator, it was found that 12.40 cm3 of aqueous solution of

sodium hydroxide was needed for a complete reaction.

(i) State a suitable indicator used for this titration. [1 mark]

……………………………………………………………………………………………………………

(ii) State the colour of the solution at the end point of the titration. [1 mark]

……………………………………………………………………………………………………………

(iii) Calculate the concentration, in mol dm3, of KHC2O4 in the aqueous solution of X.

[2 marks]

(iv) Calculate the percentage by mass of (NH4)2C2O4 in the aqueous solution of X.

[2 marks]

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- 60 -


(iv) Hitung kepekatan, dalam mol dm3, ion etanadioat C2O4

2 dalam larutan akueus X.

[2 markah]

(v) Namakan alat radas yang sesuai digunakan untuk menyukat 25 cm3 asid sulfurik.

[1 markah]

……………………………………………………………………………………………………………

(b) Apabila 25.0 cm3 larutan akueus X dititratkan dengan larutan akueus natrium hidroksida

0.05 mol dm3 dengan menggunakan penunjuk yang sesuai, didapati bahawa 12.40 cm

3 larutan akueus

natrium hidroksida diperlukan bagi tindak balas lengkap.

(i) Nyatakan penunjuk yang sesuai digunakan dalam penitratan ini. [1 markah]

……………………………………………………………………………………………………………

(ii) Nyatakan warna larutan pada takat akhir penitratan. [1 markah]

……………………………………………………………………………………………………………

(iii) Hitung kepekatan, dalam mol dm3, KHC2O4 dalam larutan akueus X. [2 markah]

(iv) Hitung peratusan mengikut jisim (NH4)2C2O4 dalam larutan akueus X. [2 markah]

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- 61 -


2 An experiment is carried out to investigate the effect of temperature on the rate of reaction.

In the experiment, 50.0 cm3 of 0.10 mol dm

3 hydrogen peroxide solution and 20.0 cm

3 of

1.0 mol dm3 sulphuric acid are added into a conical flask containing 25.0 cm

3 of 0.15 mol dm

3

potassium iodide solution, 10.0 cm3 of 0.050 mol dm

3 sodium thiosulphate solution and 10.0 cm

3 of

0.5% starch solution.

(a) The duration from the instant hydrogen peroxide solution is added to the mixture until the

appearance of the blue colouration at different temperatures is recorded in the table below.

Complete the table. [1 mark]

Temperature T/ C 18.0 28.0 38.0 48.0

Time t/s 73.0 49.0 36.0 25.0

1

t/s

–1

(i) Name a suitable apparatus used to measure 50.0 cm3 of hydrogen peroxide solution.

[1 mark]

……………………………………………………………………………………………………………

(ii) What causes the blue colouration? [1 mark]

……………………………………………………………………………………………………………

(iii) Write the equation for the reaction between hydrogen peroxide and potassium iodide.

[1 mark]

……………………………………………………………………………………………………………

(iv) What is the relationship between the rate of reaction and 1

t? [1 mark]

……………………………………………………………………………………………………………

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- 62 -


2 Satu uji kaji telah dijalankan untuk mengkaji kesan suhu terhadap kadar tindak balas.

Dalam uji kaji itu, 50.0 cm3 larutan hidrogen peroksida 0.10 mol dm

3 dan 20.0 cm

3 asid sulfurik

1.0 mol dm3 ditambahkan ke dalam satu kelalang kon yang mengandung 25.0 cm

3 larutan kalium

iodida 0.15 mol dm3, 10.0 cm

3 larutan natrium tiosulfat 0.050 mol dm

3, dan 10.0 cm

3 larutan kanji

0.5%.

(a) Tempoh masa dari ketika larutan hidrogen peroksida ditambahkan ke dalam campuran

sehingga kewujudan warna biru larutan pada suhu yang berlainan direkodkan dalam jadual di bawah.

Lengkapkan jadual ini. [1 markah]

Suhu T/ C 18.0 28.0 38.0 48.0

Masa t/s 73.0 49.0 36.0 25.0

1

t/s

–1

(i) Namakan alat radas yang sesuai digunakan untuk menyukat 50.0 cm3 larutan hidrogen

peroksida. [1 markah]

……………………………………………………………………………………………………………

(ii) Apakah yang menyebabkan warna biru larutan? [1 markah]

……………………………………………………………………………………………………………

(iii) Tulis persamaan bagi tindak balas antara hidrogen peroksida dengan kalium iodida.

[1 markah]

……………………………………………………………………………………………………………

(iv) Apakah hubungan antara kadar tindak balas dengan 1

t? [1 markah]

……………………………………………………………………………………………………………

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- 63 -


(b) Plot a graph of 1

tagainst T. [2 marks]

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- 64 -


(c) Based on the graph,

(i) state the effect of temperature on the rate of reaction. [1 mark]

…………………………………………………………...…………………………………..…………...

(ii) compare the rates of the reaction at 30 C and 40 C. Explain your answer. [2 marks]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

(d) Describe a method to determine the appearance of the blue colouration. [2 marks]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

(e) Suggest an experiment to study the effect of concentration of hydrogen peroxide on the rate of

reaction. [3 marks]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

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(c) Berdasarkan graf itu,

(i) nyatakan kesan suhu terhadap kadar tindak balas. [1 markah]

…………………………………………………………...…………………………………..…………...

(ii) bandingkan kadar tindak balas pada 30 C dan 40 C. Jelaskan jawapan anda.

[2 markah]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

(d) Perihalkan kaedah untuk menentukan kemunculan warna biru larutan. [2 markah]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

(e) Cadangkan satu uji kaji untuk mengkaji kesan kepekatan hidrogen peroksida terhadap kadar

tindak balas. [3 markah]

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

…………………………………………………………...…………………………………..…………...

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- 66 -


3 When water is added to a white solid U, a solution containing Al3+

, NH4+ and SO4

2 ions is

obtained. The scheme below shows some observations obtained when certain reagents are added to

the white solid U and its aqueous solution.

(a) What is the colour of an aqueous solution of U? [1 mark]

…………………………………………………………...…………………………………..…………...

Using Appendix A and Appendix B, answer the following questions.

(b) State the observations (i), (ii), (iii), (iv), (v) and (vi). [6 marks]

(i) ……….……………………………………………………………………………………

(ii) ……………….……………………………………………………………………………

(iii) ……….……………………………………………………………………………………

(iv) ……….……………………………………………………………………………………

(v) ……….……………………………………………………………………………………

(vi) ……….……………………………………………………………………………………

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(iv) White solid U

Aqueous solution of U

White precipitate

Colourless

solution

White precipitate

Gas W

(i)

(ii)

White fumes

Na2CO3(aq)

Water

Pb(NO3)2(aq)

NH3(aq) Ba(NO3)2(aq)

Dilute

HNO3

K2CrO4(aq)

NaOH(aq)

Excess

NaOH(aq)

Gas Z

Gases X and Y

Nessler

reagent

II

I

Δ

Δ

(iii) (v)

Colourless

solution

(iv)

- 67 -


3 Apabila air ditambahkan kepada satu pepejal putih, U, satu larutan mengandung ion Al3+

, ion

NH4+ dan ion SO4

2 diperoleh. Skema di bawah menunjukkan beberapa pemerhatian yang diperoleh

apabila reagen tertentu ditambahkan kepada pepejal putih U dan larutan akueusnya.

(a) Apakah warna larutan akueus U? [1 markah]

…………………………………………………………...…………………………………..…………...

Dengan menggunakan Lampiran A dan Lampiran B, jawab soalan yang berikut.

(b) Nyatakan pemerhatian (i), (ii), (iii), (iv), (v), dan (vi). [6 markah]

(i) ……….……………………………………………………………………………………

(ii) ……………….……………………………………………………………………………

(iii) ……….……………………………………………………………………………………

(iv) ……….……………………………………………………………………………………

(v) ……….……………………………………………………………………………………

(vi) ……….……………………………………………………………………………………

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(iv) Pepejal putih U

Larutan akueus U

Mendakan putih

Larutan tak

berwarna

Mendakan putih

Gas W

(i)

(ii)

Wasap putih

Na2CO3(ak)

Air

Pb(NO3)2(ak)

NH3(ak) Ba(NO3)2(ak)

HNO3

cair

K2CrO4(ak)

NaOH(ak)

NaOH(ak)

berlebihan

Gas Z

Gas X dan gas Y

Reagen

Nessler

II

I

Δ

Δ

(iii) (v)

Larutan tak

berwarna

(iv)

- 68 -


(c) Name the gases W, X, Y and Z. [4 marks]

W:….……………………………………………………………….……………………..……...............

X:………………………………………………………………….……………………..……………….

Y:………………………………………………………………….………………..…………………….

Z: ………………………………………………………………….………………..…………................

(d) Name the reagents I and II, and state the conditions where appropriate. [2 marks]

I: …………………………………………………………………………………………..……………..

II:…………………………………………………………………………………………………………

(e) Describe a method to test gas W. [2 marks]

……………………………………………………………………………………………..……………..

....…………………………………………………………………………………………………………

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- 69 -


(c) Namakan gas W, X, Y, dan Z. [4 markah]

W:….……………………………………………………………….……………………..……...............

X:………………………………………………………………….……………………..……………….

Y:………………………………………………………………….………………..…………………….

Z: ………………………………………………………………….………………..…………................

(d) Namakan reagen I dan II, dan nyatakan keadaan di mana-mana yang berkenaan. [2 markah]

I: …………………………………………………………………………………………..……………..

II:…………………………………………………………………………………………………………

(e) Perihalkan satu kaedah untuk menguji gas W. [2 markah]

……………………………………………………………………………………………..……………..

....…………………………………………………………………………………………………………

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- 70 -


Appendix A

Table of Cations Reactions

NaOH(aq) NH3(aq) Na2CO3(aq) K4Fe(CN)6(aq) Na2HPO4(aq) H2S in acid medium

H2S in alkaline medium or (NH4)2S Others reagen

Al3+ White precipitate

soluble in excess.

White precipitate. White precipitate. White precipitate,

soluble in mineral acid and NaOH,

insoluble in

CH3COOH.

White precipitate. (a) Aluminon reagent: red precipitate.

(b) CH3COONa: no precipitate; white precipitate when boiled.

(c) K2CrO4: orange yellow precipitate,

dissolve in mineral asid.

Ba2+ White precipitate in concentrated

solution

White precipitate. White precipitate, soluble in HNO3 or

HCl.

(a) Dilute H2SO4 or CaSO4(aq): white precipitate.

(b) (NH4)2C2O4: white precipitate,

dissolve in hot CH3COOH. (c) K2CrO4: yellow precipitate.

Ca2+ White precipitate. White precipitate. White precipitate in

excess reagent. (NH4)2C2O4: white precipitate, insoluble

in CH3COOH.

Cr3+ Greyish green precipitate, soluble

in excess to form

green solution.

Greyish green precipitate soluble in

excess to form purple

solution.

Greyish green precipitate.

Green precipitate, soluble in mineral

acids.

Greyish green precipitate.

(a) Excess NaOH + H2O2: yellow solution.

(b) Acidified solution + H2O2: blue

solution blue precipitate yellow solution.

Cu2+ Blue precipitate,

turns black when

heated.

Blue precipitate,

soluble in excess to

produce dark blue solution. Soluble in

NH4Cl.

Blue precipitate,

turns black when

heated.

Redish brown

precipitate soluble

in excess NH3(aq) to produce blue

solution.

Blue precipitate. Black precipitate,

soluble in hot

HNO3.

Black precipitate. (a) SCN : black precipitate.

(b) KI: white precipitate in brown

solution.

Fe2+

Dirty green

precipitate.

Dirty green precipitate,

soluble in NH4Cl.

Dirty green

precipitate.

Blue precipitate. Black precipitate. (a) K3Fe(CN)6(aq): dark blue precipitate.

(b) KMnO4/H+: decolourisation at room

temperature.

Fe3+ Brown precipitate. Brown precipitate. Brown precipitate. Dark blue

precipitate.

Yellowish white

precipitate, soluble in mineral acids,

insoluble in

CH3COOH.

Yellow precipitate. Black precipitate. (a) SCN : blood red solution.

(b) K3Fe(CN)6: brown solutin.

(c) KI: brown solution/yellow/black precipitate.

(d) K2CrO4: orange brown precipitate. (e) CH3COONa: red solution, brown

precipitate when heated.

Cation

Reagent

- 71 -


Lampiran A

Jadual bagi Tindak Balas Kation

NaOH(ak) NH3(ak) Na2CO3(ak) K4Fe(CN)6(ak) Na2HPO4(ak) H2S dalam medium

berasid

H2S dalam medium beralkali atau

(NH4)2S Reagen lain

Al3+ Mendakan putih,

larut dalam berlebihan.

Mendakan putih. Mendakan putih. Mendakan putih,

larut dalam asid mineral dan NaOH,

tak larut dalam

CH3COOH.

Mendakan putih. (a) Reagen Aluminon: mendakan

merah. (b) CH3COONa: tiada mendakan;

mendakan putih apabila dididihkan.

(c) K2CrO4: mendakan kuning jingga, larut dalam asid mineral.

Ba2+ Mendakan putih

dalam larutan pekat. Mendakan putih. Mendakan putih,

larut dalam HNO3

atau HCl.

(a) H2SO4 cair atau CaSO4(ak):

mendakan putih.

(b) (NH4)2C2O4: mendakan putih, larut dalam CH3COOH panas.

(c) K2CrO4: mendakan kuning.

Ca2+ Mendakan putih. Mendakan putih. Mendakan putih

dalam berlebihan. (NH4)2C2O4: mendakan putih, tak larut

dalam CH3COOH.

Cr3+ Mendakan hijau

kelabu, larut dalam

berlebihan membentuk larutan

hijau.

Mendakan hijau

kelabu, larut dalam

berlebihan membentuk larutan ungu.

Mendakan hijau

kelabu. Mendakan hijau,

larut dalam asid

mineral.

Mendakan hijau

kelabu.

(a) NaOH berlebihan + H2O2: larutan

kuning.

(b) Asidkan larutan + H2O2: larutan

biru mendakan biru larutan

kuning.

Cu2+ Mendakan biru,

menjadi hitam apabila dipanaskan.

Mendakan biru, larut

dalam berlebihan membentuk larutan

biru tua. Larut dalam

NH4Cl.

Mendakan biru,

menjadi hitam apabila

dipanaskan.

Mendakan coklat

kemerahan, larut dalam NH3 (ak)

berlebihan

membentuk larutan biru.

Mendakan biru. Mendakan hitam,

larut dalam HNO3 panas.

Mendakan hitam. (a) SCN-: mendakan hitam.

(b) KI: mendakan putih dalam larutan coklat.

Fe2+

Mendakan hijau

kotor.

Mendakan hijau kotor,

larut dalam NH4Cl.

Mendakan hijau

kotor.

Mendakan biru. Mendakan hitam. (a) K3Fe(CN)6: mendakan biru tua.

(b) KMnO4/H+: penyahwarnaan pada

suhu bilik.

Fe3+ Mendakan coklat. Mendakan coklat. Mendakan coklat. Mendakan biru tua. Mendakan putih kekuningan, larut

dalam asid mineral,

tak larut dalam CH3COOH.

Mendakan kuning. Mendakan hitam. (a) SCN-: larutan merah darah.

(b) K3Fe(CN)6: larutan coklat. (c) KI: larutan coklat/ kuning/

mendakan hitam.

(d) K2CrO4: mendakan coklat jingga. (e) CH3COONa: larutan merah,

mendakan coklat apabila dididihkan.

Kation

Reagen

- 72 -


NaOH(aq) NH3(aq) Na2CO3(aq) K4Fe(CN)6(aq) Na2HPO4(aq) H2S in acid medium H2S in alkaline

medium or (NH4)2S Others reagent

Mg2+ White precipitate,

soluble in NH4Cl.

White precipitate,

soluble in NH4Cl.

White precipitate,

soluble in NH4Cl. White precipitate,

soluble in mineral acid.

(a) Magneson reagent + NaOH: blue

precipitate. (b) Na3PO4: white precipitate.

Mn2+ White precipitate,

turns brown.

White precipitate,

turns brown, soluble in

NH4Cl.

Yellowish brown

precipitate. Yellowish brown

precipitate turns

brown when heated.

Yellowish brown

precipitate.

(a) Sodium bismutate + HNO3: violet

solution.

(b) PbO2 + HNO3 (conc): violet solution.

(c) K2S2O8 + AgNO3: violet solution.

(d) NaClO + NaO: dark brown precipirate.

Ni2+ Green precipitate.

Green precipitate,

soluble in excess

forms blue solution. Soluble in NH4Cl.

Green precipitate. Green precipitate. Green precipitate. Black precipitate. (a) Dimetilglioksima reagent + NH3:

red precipitate.

(b) NaClO + NaOH: black precipitate.

Pb2+ White precipitate,

soluble in excess.

White precipitate. White precipitate. White precipitate. White precipitate. Black precipitate. Black precipitate. (a) Dilute HCl: white precipitate,

soluble when heated; reforms when cool.

(b) Dilute H2SO4: White precipitate,

soluble in (NH4)2C2O4. (c) KI: yellow precipitate, soluble

when is heated, reforms when cool.

(d) K2CrO4: yellow precipitate. (e) NaClO: dark brown precipitate.

Zn2+ White precipitate,

soluble in excess.

White precipitate,

soluble in excess,

soluble in NH4Cl.

White precipitate. White precipitate,

soluble in alkali,

insoluble in mineral acid.

White precipitate,

soluble in NaOH,

mineral acid or NH4Cl.

White precipitate. K3Fe(CN)6: orange brown precipitate.

NH4+ Pungent gas

liberated when

heated.

Pungent gas liberated

when heated. (a) Nessler reagent: brown precipitate.

(b) Heated with NaOH, gases evolved

tested with concentrated HCl: white fume.

Cation

Reagent

- 73 -


NaOH(ak) NH3(ak) Na2CO3(ak) K4Fe(CN)6(ak) Na2HPO4(ak) H2S dalam medium

berasid

H2S dalam medium

beralkali atau

(NH4)2S Reagen lain

Mg2+ Mendakan putih,

larut dalam NH4Cl.

Mendakan putih,

larut dalam NH4Cl.

Mendakan putih,

larut dalam NH4Cl. Mendakan putih,

larut dalam asid

mineral.

(a) Reagen Magneson + NaOH:

mendakan biru.

(b) Na3PO4: mendakan putih.

Mn2+ Mendakan putih bertukar menjadi

coklat.

Mendakan putih bertukar menjadi

coklat. Larut dalam

NH4Cl.

Mendakan coklat kekuningan.

Mendakan coklat kekuningan menjadi

coklat apabila

dipanaskan.

Mendakan coklat kekuningan.

(a) Natrium bismutat + HNO3: larutan ungu/lembayung.

(b) PbO2 + HNO3 pekat: larutan ungu/

lembayung. (c) K2S2O8 + AgNO3: larutan ungu/

lembayung.

(d) NaClO: mendakan coklat tua.

Ni2+ Mendakan hijau. Mendakan hijau, larut dalam berlebihan

membentuk larutan

biru muda. Larut dalam NH4Cl.

Mendakan hijau. Mendakan hijau. Mendakan hijau. Mendakan hitam. (a) Reagen dimetilglioksima + NH3: mendakan merah.

(b) NaClO + NaOH: mendakan hitam.

Pb2+ Mendakan putih,


Mendakan putih. Mendakan putih. Mendakan putih. Mendakan putih. Mendakan hitam. Mendakan hitam. (a) HCl cair: mendakan putih, larut

apabila panas; terbentuk semula apabila disejukkan.

(b) H2SO4 cair: mendakan putih,

larut dalam (NH4)2C2O4. (c) KI: mendakan kuning, larut

apabila panas; terbentuk semula

apabila disejukkan. (d) K2CrO4: mendakan kuning.

(e) NaClO: mendakan coklat tua.

Zn2+ Mendakan putih,

larut dalam

berlebihan.

Mendakan putih,


Larut dalam NH4Cl.

Mendakan putih. Mendakan putih,

larut dalam alkali,

tak larut dalam

asid mineral.

Mendakan putih,

larut dalam NaOH,

NH4Cl, atau asid

mineral

Mendakan putih. K3Fe(CN)6: mendakan coklat jingga.

NH4+ Gas berbau hancing

dibebaskan apabila dipanaskan.

Gas berbau hancing

dibebaskan apabila dipanaskan.

(a) Reagen Nessler: mendakan

coklat. (b) Panaskan dengan NaOH, uji gas

dengan HCl pekat: wasap putih.

Kation

Reagen

- 74 -


Appendix B

Table of Anion Reactions

Dilute HCl or

H2SO4 Concentrated H2SO4

BaCl2(aq) or

Ba(NO3)2(aq) AgNO3(aq) Pb(NO3)2(aq) atau

Pb(CH3COO)2(aq) FeCl3(aq) Others reagent

HCOO Choking gas is

liberated.

Gas burned with a blue

flame is liberated. White precipitate turns

black. Dark red solution; brown


(a) KMnO4/H+: decolouration.

(b) CH3CH2OH + a little concentrated H2SO4: fragrant smell

CH COO3

Gas smell of vinegar is

released when heated.

Gas of vinegar smell is

released. White precipitate in

concentrated solution,

soluble in HNO3 or NH3(aq).

Red solution; brown


(a) CH3CH2OH + a little concentrated H2SO4:

fragrant smell.

(b) Sodalime: gas burned with blue flame without soot.

C H COO6 5

White precipitate,

soluble in hot water,

white crystal formed upon cooling.

White precipitate,

soluble in hot water;

white crystal formed upon cooling.

White precipitate,

soluble in hot water or

NH3(aq).

White precipitate. Yellowish-brown

precipitate.

(a) CH3CH2OH + a little concentrated H2SO4:

fragrant smell.

(b) Sodalime: gas burned with yellow flame without soot.

C O2 42 Gas burned with blue

flame and gas turned lime

water chalky when

heated.

White

precipitate,

soluble in HCl,

HNO3 or H2SO4.

White precipitate,

soluble in HNO3 or

NH3(aq).

White precipitate,

soluble in HNO3. (a) KMnO4/H

+: decolourised when heated.

(b) CaCl2(aq): when precipitate.

Cl White fume is formed. White precipitate,

insoluble in HNO3 but soluble in NH3(aq).

White precipitate,

soluble in hot water; or concentrated HCl; white

crystal formed upon

cooling.

MnO2(s) + H2SO4 (conc): greenish-yellow gas

is liberated.

Br Redish-brown gas is liberated.

Light yellow precipitate, insoluble

in dulute HNO3 or

NH3(aq).

White precipitate, soluble in hot water,

white crystal formed

upon cooling.

(a) MnO2(s) + H2SO4 (conc): redish-brown gas is liberated.

(b) Cl2 /NaOCl(aq) + CCl4: redish-brown

colouration at the bottom layer. (c) Concentrated HNO3 and heated: redish-

brown gas is liberated.

I Brown fume is formed; purple fume formed when

heated.

Yellow precipitate, insoluble in dilute

HNO3 or NH3(aq).

Yellow precipitate, soluble in hot water;

yellow crystal formed

upon cooling.

Redish brown solution. (a) Cl2 water/NaOCl(aq)/Br2 water + CCl4: redish violet colouration formed at the

bottom layer.

(b) NaNO2(aq) + dilute asid: brown solution and brown gas is liberated.

Anion

Reagent

- 75 -


Lampiran B

Jadual bagi Tindak Balas Anion

HCl cair atau H2SO4 cair H2SO4 pekat

BaCl2(ak) atau Ba(NO3)2(ak) AgNO3(ak)

Pb(NO3)2(ak) atau Pb(CH3COO)2(ak) FeCl3(ak) Reagen lain

HCOO Gas berbau sengit

dibebaskan.

Gas terbakar

dengan nyalaan biru

dibebaskan.

Mendakan putih

menjadi hitam. Larutan merah tua;

mendakan coklat

apabila dipanaskan.

(a) KMnO4/H+: penyahwarnaan.

(b) CH3CH2OH + sedikit H2SO4 pekat:

bau buah-buahan/wangi.

CH COO3

Gas berbau cuka

dibebaskan apabila

dipanaskan.

Gas berbau cuka

dibebaskan. Mendakan putih

dalam larutan pekat,

larut dalam HNO3

atau NH3(ak).

Larutan merah;

mendakan coklat

apabila dididihkan.

(a) CH3CH2OH + sedikit H2SO4 pekat:

bau buah-buahan/wangi.

(b) Kapur soda: gas terbakar dengan

nyalaan biru tanpa jelaga.

C H COO6 5

Mendakan putih, larut dalam air panas;

hablur putih apabila

disejukkan.

Mendakan putih, larut dalam air panas;

hablur putih apabila

disejukkan.

Mendakan putih, larut dalam air panas

atau NH3(ak).

Mendakan putih. Mendakan coklat kekuningan.

(a) CH3CH2OH + sedikit H2SO4 pekat: bau buah-buahan/wangi.

(b) Kapur soda: gas terbakar dengan

nyalaan kuning berjelaga.

C O2 42 Gas terbakar dengan

nyalaan biru dan gas

mengeruhkan air kapur

apabila dipanaskan.

Mendakan putih,

larut dalam HCl,

HNO3 , atau

H2SO4.

Mendakan putih,

larut dalam HNO3

atau NH3(ak).

Mendakan putih,

larut dalam HNO3. (a) KMnO4/H

+: dinyahwarnakan apabila

dipanaskan.

(b) CaCl2(ak): mendakan putih.

Cl Wasap putih dibebaskan. Mendakan putih,

tidak larut dalam

HNO3 tetapi larut dalam NH3(ak).

Mendakan putih,

larut dalam air panas

atau HCl pekat; hablur putih apabila

disejukkan.

MnO2(p) + H2SO4 pekat: gas kuning

kehijauan dibebaskan.

Br Gas coklat kemerahan

dibebaskan. Mendakan kuning

pucat, tidak larut dalam HNO3 cair

atau NH3(ak).

Mendakan putih,

larut dalam air panas; hablur putih apabila

disejukkan.

(a) MnO2(p) + H2SO4 pekat: gas

coklat kemerahan dibebaskan. (b) Air Cl2 /NaOCl(ak) + CCl4: lapisan

bawah berwarna coklat kemerahan.

(c) HNO3 pekat dan panas: gas coklat kemerahan dibebaskan.

I Wasap coklat dibebaskan;

wasap ungu dibebaskan apabila dipanaskan.

Mendakan kuning,

tidak larut dalam HNO3 cair atau

NH3(ak).

Mendakan kuning,

larut dalam air panas; hablur kuning apabila

disejukkan.

Larutan coklat

kemerahan.

(a) Air Cl2/NaOCl/air Br2 + CCl4: lapisan

bawah berwarna ungu. (b) NaNO2(ak) + asid cair: larutan coklat

dan gas coklat dibebaskan.

Anion

Reagen

- 76 -


Dilute HCl or

H2SO4 Concentrated H2SO4

BaCl2(aq) or

Ba(NO3)2(aq) AgNO3(aq) Pb(NO3)2(aq) or

Pb(CH3COO)2(aq) FeCl3(aq) Others reagent

CO32 Gas liberated can turn

lime water chalky.

Gas liberated can turn

lime water chalky.

White

precipitate,

soluble in HCl or dilute HNO3.

White precipitate

turned yellow in excess;

become brown when heated.

White precipitate,

soluble in dilute HNO3.

Brown precipitate;

gas liberated which turn

lime water chalky.

MgSO4(aq)/MgCl2(aq): white precipitate.

SO32 Brimstone smell gas/

burnt sulphur, gas decolourise

KMnO4/H+.

Brimstone smell gas/

burnt sulphur, gas decolourise KMnO4/H

+.

White

precipitate, soluble in HCl

or HNO3.

White precipitate,

soluble in HNO3,

NH3(aq), or SO32 in

excess; turn black


White precipitate,

soluble in dilute HNO3.

Red solution; brown


(a) I2: decolourisation.

(b) KMnO4/H+: decolourisation.

(c) K2Cr2O7/H+: green solution.

S O2 32 Yellow precipitate;

brimstone smell gas/

burnt sulphur, gas

decolourise KMnO4/H+.

Yellow precipitate; brimstone smell gas/

burnt sulphur, gas

decolourise KMnO4/H+.

White precipitate in

concentrated

solution.

White precipitate turn to yellow and then brown

and finally black; white

precipitate soluble in

excess S2O32 .

White precipitate,

soluble in excess S2O32 ;

turn black precipitate

when heated.

Purplish solution decolourise.

(a) I2: decolourisation. (b) KMnO4/H

+: decolourisation.

(c) K2Cr2O7/H+: green solution.

(d) Ammonium molybdate + H2SO4: blue ring.

S2 A foul (rotten egg),

smell was liberated,

blackening Pb(CH3COO)2 paper.

A foul (rotten egg)

smell was liberated,

blackening Pb(CH3COO)2 paper,

yellow precipitate.

Black precipitate,

soluble in hot HNO3.

Black precipitate. A yellow sediment in an

acidic medium. A black

sediment in an alkaline medium.

(a) KMnO4/H+: decolourisation,

yellow precipitate.

(b) K2Cr2O7/H+: green solution,

yellow precipitate.

SO42 White

precipitate,

insoluble in

HCl or HNO3.

White precipitate, soluble in aqueous

ammonium ethanoate.

NO2 Brown fume liberated. Brown fume liberated. White precipitate in

concentrated solution,

soluble in HNO3 or

NH3.

Redish brown precipitated/solution

when heated.

(a) KMnO4/H+: decolourisation.

(b) K2Cr2O7/H+: green solution.

(c) FeSO4 + H2SO4: brown ring.

(d) Devarda alloy: pungent gas. (e) KI + dilute acid: brown sol.

NO3 Brown fume liberated. (a) FeSO4 + H2SO4: brown ring.

(b) Devarda alloy: pungent gas.

(c) Concentrated H2SO4 pekat + Cu: brown fume, blue solution.

MnO4 (a) C2O4

2-/SO32-/S2O3

2-/NO2

- with H+:

decolourisation.

(b) S2-: decolourisation, yellow precipitate.

Anion

Reagent

- 77 -


HCl cair atau

H2SO4 cair H2SO4 pekat BaCl2(ak) atau

Ba(NO3)2(ak) AgNO3(ak) Pb(NO3)2(ak) atau

Pb(CH3COO)2(ak) FeCl3(ak) Reagen lain

CO32 Gas yang mengeruhkan

air kapur dibebaskan.

Gas yang mengeruhkan


Mendakan putih,

larut dalam HCl

atau HNO3 cair.

Mendakan putih

menjadi kuning dalam

berlebihan; menjadi coklat apabila

dididihkan.

Mendakan putih,

larut dalam HNO3 cair.

Mendakan coklat;

gas yang mengeruhkan


MgSO4(ak)/MgCl2(ak): mendakan putih.

SO32 Gas berbau belerang/

sulfur terbakar, gas menyahwarnakan

KMnO4/H+.

Gas berbau belerang/

sulfur terbakar, gas menyahwarnakan

KMnO4/H+.

Mendakan putih,

larut dalam HCl atau HNO3.

Mendakan putih,

larut dalam HNO3, NH3, atau SO3

2- berlebihan;

mendakan hitam

apabila dididihkan.

Mendakan putih,

larut dalam HNO3.

Larutan merah;

mendakan coklat apabila dididihkan.

(a) I2: penyahwarnaan.

(b) KMnO4/H+: penyahwarnaan.

(c) K2Cr2O7/H+: larutan hijau.

S O2 32 Mendakan kuning; gas

berbau belerang/sulfur terbakar,

gas menyahwarnakan

KMnO4/H+.

Mendakan kuning;

gas berbau belerang/ sulfur terbakar,

gas menyahwarnakan

KMnO4/H+.

Mendakan putih

dalam larutan pekat.

Mendakan putih kepada

kuning kepada coklat kepada hitam;

mendakan putih larut

dalam S2O32- berlebihan.

Mendakan putih,

larut dalam S2O32-

berlebihan;

mendakan hitam

apabila dididihkan.

Larutan ungu luntur

apabila dibiarkan.

(a) I2: penyahwarnaan.

(b) KMnO4/H+: penyahwarnaan.

(c) K2Cr2O7/H+: larutan hijau.

(d) Ammonium molibdat + H2SO4 pekat:

cincin biru.

S2 Gas berbau telur busuk dibebaskan,

gas menghitamkan

kertas Pb(CH3COO)2.

Gas berbau telur busuk dibebaskan,

gas menghitamkan

kertas Pb(CH3COO)2, mendakan kuning.

Mendakan hitam, larut dalam HNO3

panas.

Mendakan hitam. Mendakan kuning dalam medium berasid.

Mendakan hitam

dalam medium beralkali.

(a) KMnO4/H+: penyahwarnaan,

mendakan kuning.

(b) K2Cr2O7/H+: larutan hijau,

mendakan kuning.

SO42 Mendakan putih,

tidak larut dalam HCl atau HNO3.

Mendakan putih,

larut dalam ammonium etanoat akueus.

NO2 Wasap coklat

dibebaskan.

Wasap coklat

dibebaskan. Mendakan putih

dalam larutan pekat,

larut dalam HNO3 atau NH3.

Mendakan/larutan coklat

kemerahan apabila

dipanaskan.

(a) KMnO4/H+: penyahwarnaan.

(b) K2Cr2O7/H+: larutan hijau.

(c) FeSO4 + H2SO4 cair: cincin coklat. (d) Aloi Devarda: gas berbau hancing.

(e) KI + asid cair: larutan coklat.

NO3 Wasap coklat

dibebaskan. (a) FeSO4 + H2SO4 pekat: cincin coklat.

(b) Aloi Devarda: gas berbau hancing. (c) H2SO4 pekat + Cu: wasap coklat;

larutan biru.

MnO4 (a) C2O4

2-/SO32-/S2O3

2-/NO2

- dengan H+:

penyahwarnaan. (b) S2-: penyahwarnaan, mendakan kuning.

Anion

Reagen

- 78 -


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