2007 sbp with answer

4541/1 [Lihat sebelah

SULIT

SULIT 4541/1

4541/1

Kimia

Kertas 1

Ogos

2007

1 jam

BAHAGIAN SEKOLAH

KEMENTERIAN PELAJARAN MALAYSIA

______________________________________________

PEPERIKSAAN PERCUBAAN SPM 2007

KIMIA

Kertas 1

Satu jam lima belas minit

JANGAN BUKA KERTAS SOALAN INI HINGGA DIBERITAHU

1. Kertas soalan ini mengandungi 50 soalan. 2. Jawab semua soalan 3. Jawab dengan menghitamkan ruangan yang betul pada kertas jawapan 4. Bagi setiap soalan hitamkan satu ruangan sahaja 5. Sekiranya anda hendak menukar jawapan, padamkan tanda yang telah dibuat.

Kemudian hitamkan jawapan yang baru.

6. Rajah yang mengiringi soalan tidak dilukiskan mengikut skala. 7. Anda dibenarkan menggunakan kalkulator saintifik yang tidak boleh

diprogramkan.

Kertas soalan ini mengandungi 19 halaman bercetak

http://cikguadura.wordpress.com/

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2

1 Which of the following processes, proved the kinetic theory of matter?

A

B

C

D

Diffusion

Photosynthesis

Respiration

Neutralization

2 Which of the following is a chemical formula of ammonium sulphate?

A

B

C

D

NH4SO4

(NH4)2SO4

(NH3)2SO4

(NH4)3(SO4)2

3 Elements in the Periodic Table are arranged according to an increase in

A

B

C

D

proton number

nucleon number

relative atomic mass

relative molecular mass

4 Which of the following substances is a covalent compound?

A

B

C

D

Copper

Ammonia

Lead(II) oxide

Sodium chloride

5 Which of the following substances is an electrolyte?

A

B

C

D

Hydrogen chloride in methyl benzene

Molten aluminium oxide

Glucose solution

Copper(II) carbonate powder

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3

6 Which of the following statements is true about alkali?

A

B

C

D

Weak alkali is an alkali that undergoes high rate of ionization.

Strong alkali has low pH value

Alkalis are bases that are soluble in water.

Alkalis are not corrosive

7 Which of the following is a soluble salt?

A

B

C

D

Lead(II) iodide

Copper(II) carbonate

Barium sulphate

Sodium hypochlorite

8 The body of the car shown in the diagram below is made of alloy T.

What is alloy T?

A

B

C

D

Steel

Brass

Bronze

Duralumin

Alloy T

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4

9 Which of the homologous series is correctly paired to its functional group?

Homologous series Functional groups

A

Ester

B

Alkene

C

Alcohol

D

Carboxylic acid

10 Which of the following statements correctly explains the meaning of effective collision?

A

B

C

D

The collision which takes place before reaction.

The collision where its energy is less than the activation energy.

The collision that can causes reaction.

The collision that has the highest energy.

11

Which of the following is true about the substances?

A

B

C

D

Reducing agent

Oxidising agent

Dehydration agent

Hydration agent

Bromine water

Acidified potassium manganate(VII)

Acidified potassium dichromate(VI)

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5

12 Which of the following processes occurs when ice changes to water ?

A

B

C

D

Endothermic

Exothermic

Neutralization

Freezing

13 Paracetamol is used for

A

B

C

D

reducing pain

reducing anxiety

destroying of bacteria

controlling the level of glucose in blood

14 The diagram below shows the molecular formula of glucose.

What is the empirical formula for glucose?

A

B

C

D

CH2O

CH2O2

C2H4O2

C6H12O6

15

Which of the following is the atomic structure of lithium atom, ?

A

B

C

D

3p 3p

4p 4p

C6H12O6

7

3

Li

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6

16 The figure shows three elements in Period 3 of the Periodic Table.

X Y Z

Which of the following is true about the properties of oxide formed?

A

B

C

D

The oxide of Z is basic

The oxide of Y is acidic

The formula of oxide Y is YO

The oxide of X reacts with an acid to form salt and water

17 Which of the following substances is made up of ions?

A

B

C

D

Sulphur

Naphthalene

Sulphur trioxide

Potassium chloride

18 Which of the following ions are present in copper(II) sulphate solution?

A

B

C

D

Hydrogen ions and hydroxide ions

Copper(II) ions and sulphate ions

Copper(II) ions ,hydrogen ions, suphide ions and oxide ions

Copper(II) ions, hydrogen ions, sulphate ions and hydroxide ions

19 Dry hydrogen chloride gas is passed through methyl benzene for a few minutes. Which

of the following statements is true about the liquid produced?

I

II

III

IV

A

B

C

D

it has a pH value of less than 7

it consists of hydrogen chloride molecules

it changes blue litmus to red

it does not conduct electric current

I and III only

II and IV only

I, II and III only

IV only

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7

20 The diagram shows part of a polymer molecule

CH3 H CH3 H CH3 H

C C C C C C

H H H H H H

Which is its monomer?

A

B

C

D

21 Nitric acid will change to nitrate salt when hydrogen ions are replaced by

I

II

III

IV

A

B

C

D

copper ion

hydroxide ion

carbonate ion

ammonium ion

I and II only

I and IV only

II and IV only

I, III and IV only

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8

22 The graph shows the volume of carbon dioxide gas produced against time for the

reaction of calcium carbonate and sulphuric acid.

The gradient of the graph decreases with time because

A

B

C

D

catalyst is not used

volume of mixture decreases

temperature of reaction decreases

concentration of sulphuric acid decreases

23 The equation below shows a chemical reaction.

Based on the equation given, name the reaction.

A

B

C

D

Hydrogenation

Polymerization

Halogenation

Substitution

Volume of CO2

gas / cm3

Time / second

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9

24 The diagram below shows the electrolysis process of copper(II) sulphate solution using

copper as an electrode.

Which of the following substances are oxidized and reduced in this cell?

Oxidised Reduced

A Hydroxide ion Copper(II) ion

B Hydroxide ion Copper atom

C Copper atom Copper(II) ion

D Copper atom Hydrogen ion

25 The reaction between nitrogen and oxygen can be represented by the following equation:

N2 (g) + O2(g) 2NO(g) H = +181 kJ

Which of the following energy level diagrams represent the above reaction?

A

B

C

D

Copper

Copper(II) sulphate

solution

H = +181 kJ

2NO(g)

Energy

Energy

N2 (g) + O2(g)

2NO(g)

H = +181 kJ

N2 (g) + O2(g)

2NO(g)

H = +181 kJ

Energy

2NO(g)

N2 (g) + O2(g)

H = +181 kJ

Energy

N2 (g) + O2(g)

H = +181 kJ

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10

26 The diagram shows a label on a bottle of orange juice.

X is one of the important ingredients to make orange juice last longer.

What is X?

A

B

C

D

Sodium nitrite

Sodium nitrate

Ascorbic acid

Benzoic acid

27 The figure shows the arrangement of particles of a substance that undergoes the change

of state through process X

What is process X ?

A

B

C

D

Melting

Boiling

Freezing

Sublimation

SUKARAMAI ORANGE JUICE

Ingredients: water, sugar, X , sulphur dioxide, aspartame,

vitamin A and D

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11

28 The equation below shows the reaction between sulphuric acid and sodium hydroxide

solution.

H2SO4 + 2KOH K2SO4 + 2H2O

What is the number of moles of sodium sulphate salt produced if 0.2 mol of sodium

hydroxide is used?

A

B

C

D

0.10 mol

0.05 mol

0.22 mol

0.25 mol

29 The table shows the electron arrangements of atoms of four elements.

Which of the following is the correct arrangement of the elements according to

increasing order of electronegativity?

Element F Al Cl K

Electron

arrangement

2.7

2.8.3

2.8.7

2.8.8.1

A

B

C

D

F, Al, Cl, K

F, Cl, Al, K

K, Cl, Al, F

K, Al, Cl, F

30 The number of valence electrons of atoms X and Y are 2 and 7 respectively.

Which of the following chemical formulae and types of bonding are true for the

compound formed between X and Y?

Chemical Formula Type of Bonding

A XY2 ionic

B XY2 covalent

C X2Y ionic

D X2Y covalent

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12

31 The diagram below shows the set-up of the apparatus for electrolysis of concentrated

solution of sodium chloride

What is the product formed at the anode and cathode?

Anode Cathode

A O2 H2 B Cl2 H2 C Cl2 Na

D O2 Cl2

32 The diagram below shows 5 steps for preparing a standard solution of sodium hydroxide,

NaOH but not in correct order.

Which of the following steps is correct?

A

B

C

D

Q, S, P, R, T

R, Q, S, P, T

Q, P, S, R, T

R, Q, S, T, P

P- Transfer the solid sodium hydroxide into volume into the volumetric flask.

Q- Weigh the mass of sodium hydroxide

R- Add distilled water until the graduation mark.

S- Rinse the weighing bottle and pour the solution into the volumetric flask.

T- Shake the volumetric flask.

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13

33 The diagram below shows the test tubes containing lead(II) nitrate solution and

potassium carbonate solution but without a label. Which of the following solutions can

be used to distinguish both solutions?

I

II

III

IV

A

B

C

D

Sodium nitrate

Sodium iodide

Dilute nitric acid

Potassium sulphate

I and II only

II and IV only

II, III and IV only

I, II, III and IV

34 Which of the following is the alcohol produced from the alkaline hydrolysis of oil?

A

B

C

D

Ethane-1,2-diol

Glycerol

Cyclohexanol

Buthane-2-ol

Lead(II) nitrate

solution

Potassium carbonate

solution

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14

35

A group of students carried out an experiment to determine the rate of reaction of zinc

metal with dilute hydrochloric acid. The diagram above shows the graph for the total

volume of gas collected against time. The average rate of reaction for the whole

experiment is :

A

B

C

D

0.3 cm3/s

0.25 cm3/s

0.17 cm3/s

0.13 cm3/s

36 When a mixture of 2-butanol, CH3CHOHCH2CH3 and concentrated sulphuric acid is

heated, gas X is produced. Which of the following is the molecular structure of X?

A

B

C

D

CH3CH=CHCH3

CH3CH=C(CH3)2

(CH3)2CHCH=CH2

CH3CH2CH=CH2

37 The diagram below shows the changes of the sulphur in Contact Process.

S SO2 SO3 H2S2O7

Which of the following are the correct changes in the oxidation state of sulphur?

A

B

C

D

0 +4 +6 +6

0 +4 +6 +7

1 +3 +6 +8

1 +4 +6 +6

0 60 120 180 240 300 time / s

Volume of H2 gas / cm3

40 36

30

20 18

10

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15

38 The following equation shows the formation of water

H2(g) + O2(g) H2O(l) , H = 287 kJmol

Which of the following is true regarding the above equation?

A

B

C

D

Activation energy for the reaction is high

If 1 mole of oxygen reacts 574 kJ of heat energy is absorbed

Combustion of 1 mole of hydrogen releases 287 kJ of heat energy

1 mole of water that is formed in the reaction received 287 kJ heat energy

39

Which of the following medicines is most appropriate in treating the above symptoms or

disorders?

A

B

C

D

Chlorpromazine

Amphetamine

Tranquilisers

Barbiturates

40 Which of the following isotopes is used to detect leakage in a gas pipe.

.

A

B

C

D

Carbon 14 Cobalt 60 Sodium 24 Iodine - 131

41 34 g of ammonia consists of

[Relative molecular mass of ammonia = 17, Avogadro constant = 6.02 x 10 23

mol-1

]

I

II

III

IV

A

B

C

D

2 mole of nitrogen atoms

2 mole of ammonia molecules

1.204 X 1024

molecules

5 mole of hidrogen atoms

I and II only

I, II and III only

II, III and Iv only

I, II, III and IV only

A patient claims he always heard someone says something to him but he

didnt see anybody around him during the situation.

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16

42 Profesional cyclists usually fill their bicycle tyres with gas X which makes the bicycle

lighter.

Which of the following elements X, Y, W and Z in the Periodic Table is suitable to be

used in bicycle tyres?

X

Y W

Z

A

B

C

D

X

Y

W

Z

43 The diagram below shows the symbols of atoms D and E

Atom D reacts with atom E to form a compound. Calculate the relative molecular mass

for the compound formed.

A

B

C

D

21

43

102

113

44 Calculate the volume of sodium hydroxide of concentration 0.5 mol dm-3

needed to

neutralize 25.0 cm3 sulphuric acid of concentration 0.20 mol dm

-3.

A

B

C

D

10 cm3

20 cm3

25 cm3

50 cm3

27

D 13

16

E 8

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17

45 The table below shows the potential difference of three simple voltaic cells.

Cell Pair of metal Potential

difference(V)

Negative

terminal

I Mg and Cu 3.0 Mg

II Mg and Zn 1.5 Mg

III Zn and Fe 0.5 Zn

What is the potential difference of a simple voltaic cell for pair of iron and copper ?

A

B

C

D

0.5 V

1.0 V

1.5 V

2.5 V

46 200 cm3 of 0.1 mol dm

-3 sodium chloride solution reacts completely with excess silver

nitrate. Calculate the mass of precipitate produced.

[Relative atomic mass of: Ag, 108; Cl, 35.5]

A

B

C

D

2.78 g

2.87 g

3.78 g

3.87 g

47 The uses of substance X;

What is substances X?

A

B

C

D

Nitric acid

Sulphuric acid

Ammonia

Ammonium sulphate

To clean metals.

To produce detergents.

To make paints.

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18

48 Graph represents the decomposition of 25 cm3

hydrogen peroxide of 0.5 mol dm-3

with

manganese(IV) oxide as a catalyst at a temperature of 30oC.

Which of the following experiments will produce graph II ?

Volume of

hydrogen peroxide / cm3

Concentration of

hydrogen peroxide/

mol dm-3

Temperature of

hydrogen peroxide / oC

A 15 0.7 30

B 15 0.5 30

C 40 0.7 30

D 40 0.5 20

49 Which of the following equations represents a redox reaction?

A

B

C

D

Pb(NO3)2(aq) + CuSO4(aq) PbSO4(s) + Cu(NO3)2(aq) CH3COOH(aq) + NaOH(aq) CH3COOH(aq) + H2O(l) Mg(s) + CuSO4(aq) MgSO4(aq) + Cu(s) C2H4(g) + 3O2(g) 2CO2(g) + 2H2O(l)

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19

50 The diagram below shows the molecular formulae of two compounds A and B.

Substance X is formed when both compounds react with each other.

Which of the following set represents substance X?

Structural formula Name

A

Ethyl propanoate

B

Ethyl propanoate

C

Propyl propanoate

D

Propyl propanoate

END OF QUESTION PAPER

Compound A,

C2H5OH

Compound B,

C2H5COOH

Substance X

H H

H

H

C C C C

H H

H H H

H

O

O

C

H H

H

H

C C C C

H H

H H H

H

O

O

C

C

O

C

H

H

H

H

O

H H

H

C C H

H

H

C

C

O

C

H

H

H

H

O

H H

H

C C H

H

H

C


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NAMA:.................................................... Tingkatan :..............................

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4541/2

Kimia

Kertas 2

Ogos

2007

2 jam

BAHAGIAN SEKOLAH



KIMIA

Kertas 2

Dua jam tiga puluh minit

JANGAN BUKA KERTAS SOALAN INI SEHINGGA DIBERITAHU

1. Tuliskan nama dan tingkatan pada ruang

yang disediakan.

2. Jawab semua soalan daripada Bahagian A. Tuliskan jawapan anda dalam ruang yang

disediakan

3. Jawab satu soalan daripada Bahagian B dan satu soalan daripada Bahagian

C.Jawapan kepada bahagian B dan

Bahagian C hendaklah ditulis pada kertas

tulis.

4. Anda diminta menjawab dengan lebih terperinci untuk Bahagian B dan Bahagian

C. Jawapan mestilah jelas dan logik.

Persamaan, gambar rajah, jadual, graf dan

cara lain yang sesuai untuk menjelaskan

jawapan anda boleh digunakan.

5. Anda hendaklah menyerahkan kertas tulis dan kertas tambahan, jika digunakan

bersama-sama dengan kertas soalan.

6. Penggunaan kalkulator saintifik yang tidak boleh diprogramkan adalah dibenarkan.

Bahagian Soalan Markah

penuh

Markah

diperoleh

A

1 9

2 10

3 10

4 11

5 10

6 10

B 7 20

8 20

C

9 20

10 20

Jumlah



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2

Section A

[60 marks]

Answer all questions.

1 Table 1 shows the melting point and boiling point of four substances.

Substances Melting point/ C Boiling point/ C

P -5 67

Q -105 -38

R 80 140

S 801 1413

TABLE 1

(a) What is the physical state of P and S at room temperature?

P: ....................................................................................................................

S: ....................................................................................................................

[2 marks]

(b) Draw the arrangement of particles of P at room temperature.

[1 mark]

(c) Explain why substance Q has a low melting point and boiling point.

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

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

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

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

[2 marks]

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3

(d) Draw the set up of apparatus to determine the melting point of substance R.

[2 marks]

(e) Sketch the graph of temperature against time for substance R when it is

heated from room temperature until it reaches a temperature of 100oC.

[2 marks]

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4

2 Diagram 2 shows part of the Periodic Table of Elements. A, B, C, D, E, F, G and

H do not represent the actual symbol of the elements.

A

B C D

E F G

DIAGRAM 2

Using the letters in the Periodic Table of Elements in Diagram 2, answer the

following questions.

(a) (i) Write the electron arrangement of atom F.

. [1 mark]

(ii) Give the formula of ion F.

.... [1 mark]

(b) Arrange the elements A, B, C, D, E, F and G according to the atomic size in

ascending order.

[1 mark]

(c) Element A exists as a monoatomic gas. Explain why.

[1 mark]

(d) Element D is more reactive than element G. Explain why.

[2 marks]

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5

(e) E reacts with D to form a compound.

(i) What is the type of the compound formed?

. . [1 mark]

(ii) Draw the diagram of electron arrangement for the compound formed.

[2 marks]

(iii) State one physical property of the compound formed.

... [1 mark]

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6

3 Diagram 3 shows two types of cell.

DIAGRAM 3

(a) Write the formula of all the cations present in the copper (II) nitrate solution.

[1 mark]

(b) (i) State the observation at the cathode of cell J.

[1 mark]

(ii) Write a half equation for reaction that occurred in the cathode of cell J.

[ 1 mark] (iii) Name the reducing agent in the cell J. .. [1 mark]

(iv) Name the product formed at the anode if copper electrodes in cell J are

replaced by carbon electrodes.

... [1 mark]

Copper(II)

nitrate

solution

Cell J

V

Copper

plate Zinc plate

Cell K

Copper

electrode

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7

(c) Based on cell K,

(i) In which direction do electrons flow through the circuit in cell K? Show

your answer on Diagram 3.

[1 mark]

(ii) Name the reaction that occurs at the zinc plate.

............ [1 mark]

(iii) State the changes in oxidation number for zinc in this reaction.

........ [1 mark]

(iv) What happens to the cell voltage if the copper plate is replaced with the silver

plate?

... [1 mark]

(d ) Write overall ionic equation for the reaction.

. [1 mark]

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8

4 Table 4 shows the particulars of four different types of manufactured substances

in industry.

Types Examples Components

Glass Borosilicate Silicon dioxide, sodium oxide, calcium oxide and X

Polymer Z Vinyl chloride

Alloy Bronze Copper and Y

Composite

material W

Concrete (cement, sand and small pebbles) and

steel

TABLE 4

(a) X is a part of the borosilicate glass. What is X?

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

[1 mark]

(b) (i) Identify Y.

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

[1 mark]

(ii) Bronze is harder than pure copper. Explain why.

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

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

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

[2 marks]

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9

(c) The following diagram shows a part of molecular structure of a compound Z.

H Cl H Cl H Cl

C C C C C C

H H H H H H

(i) Draw the structure of its monomer.

[1 mark]

(ii) Compound Z is often used as a water pipe. State one advantage of this type

of pipe as compared to metal pipes.

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

[1mark]

(d) W can withstand high pressure and can support very heavy loads.

What is W?

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

[1mark]

(c) Ammonium fertilizers can be prepared by reactions between ammonia solutian

and acids.

(i) Write the chemical equation for the preparation of ammonium sulphate

fertilizer.

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

[1 mark]

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10

(ii) Urea, CO(NH2)2 is another example of ammonium fertilizers. Between urea

and ammonium sulphate, which one is more suitable for the growth of

plants? Prove it.

[Relative atomic mass: H,1; C,12; N,14; O,16; S,32]

[3 marks]

5 Diagram 5 shows the structural formulae of compounds J and K.

DIAGRAM 5

(a) State the homologous series for compounds J and K.

Compound J: .........

Compound K: ..... [2 marks]

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11

(b) Compound K can be produced from compound J under a high temperature

and pressure in the presence of a catalyst.

(i) Name compound K.

....... [1 mark]

(ii) Name the reaction.

............ [1 mark]

(c) Compound L is produced when an acidic potassium dichromate (VI)

solution is added into a test tube containing compound K.

(i) State one observation for this reaction.

....... [1 mark]

(ii) Write the molecular formula of compound L.

....... [1 mark]

(d) Compound J burns completely in excess oxygen.

(i) Write the chemical equation for the complete combustion of J.

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

[1 mark]

(ii) 5.6 g of compound J undergoes complete combustion at room

conditions. Calculate the volume of carbon dioxide gas released.

[1 mol of gas occupies 24 dm3 at room conditions;

Relative atomic mass: H,1; C,12]

[3 marks]

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12

6 A pupil carried out an experiment to determine the value of heat of neutralization.

Diagram 6 shows the set up of the apparatus used in the experiment.

The following data was obtained;

a) Why was a polystyrene cup used in this experiment?

.. [1 mark]

(b) Given that the specific heat capacity of the solution is 4.2 Jg-1o

C-1

and the

density of the solution is 1.0 gcm-3.

(i) Calculate the change of heat in the experiment.

(ii) Calculate the heat of neutralization in the experiment.

[3 marks]

Initial temperature of hydrochloric acid = 28oC

Initial temperature of sodium hydroxide solution = 28oC

Highest temperature of the mixture of product = 41oC

100 cm

3of 2.0 mol dm

-3

Sodium hydroxide solution

100 cm3of 2.0 moldm

-3

hydrochloric acid

Thermometer

DIAGRAM 6

Polystyrene cup

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13

(c) Draw the energy level diagram for the reaction.

[2 marks]

(d) Based on the experiment, what is meant by the heat of neutralisation?

....... [1 mark]

(e) The pupil repeats the experiment by replacing hydrochloric acid with

ethanoic acid. All the other conditions remain unchanged.

(i) Predict the value of the heat of neutralisation?

......... [1 mark]

(ii) Explain why?

........

....

........

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

[2 marks]

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14

Section B

[20 marks]

Answer any one question.

7 (a)

Explain why the pH values of these two acids are different.

[4 marks]

(b) The two solutions are tested with a dry red litmus paper and the results are

tabulated below:

Solution Observation

Ammonia in chloroform No change in colour

Ammonia in water Red litmus paper turns blue

Explain why only the aqueous ammonia solution turns red litmus paper

blue.

[5 marks]

(c) You are required to prepare dry zinc sulphate salt. The chemicals supplied

are

zinc nitrate solution

dilute sulphuric acid

sodium carbonate solution

Describe a laboratory experiment to prepare the salt. In your description,

include chemical equations involved.

[11 marks]

Type of acid Concentration pH value

Ethanoic acid 0.1 mol dm-3

3.0

Nitric acid 0.1 mol dm-3

1.0

SULIT 4541/2


SULIT

15

8 (a) What is meant by empirical formula?

[1 mark]

(b) A carbon compound contains 92.3% of carbon and 7.7% of hydrogen by

mass.

The relative molecular mass of this compound is 78.

Find the molecular formula of this compound.

[Relative atomic mass: C, 12; H, 1]

[5 marks]

(c) Describe how you could determine the empirical formula of magnesium oxide

in the laboratory. Your description should include

procedure of experiment

tabulation of result

calculation of the results obtained [Relative atomic mass: O,16; Mg,24]

[14 marks]

Section C

[20 marks]

Answer any one question.

9 (a) Define oxidation and reduction in term of changes in oxidation number.

[2 marks]

(b) Based on electron transfer, explain the oxidation and reduction reaction in

(i) changing of Fe2+

ions to Fe3+

ions

(ii) changing of Fe3+

ions to Fe2+

ions

Use a suitable example for each of the reaction. Include half equations in

your anwers.

[8 marks]

(c)

Describe an experiment to prove the above statement by the transfer of

electrons at a distance. In your description, include

labelled diagram which shows the set up of apparatus

procedure of experiment

observations at both electrodes

[10 marks]

Electrical energy can be produced by redox reaction.

SULIT 4541/2


SULIT

16

10 (a) (i) What is a catalyst?

(ii) State two characteristics of a catalyst.

(iii) Name one chemical process and the catalyst used in industry.

[4 marks]

(b) State two factors other than catalyst which can affect the rate of reaction.

Based on collision theory, explain how the factors that you mentioned can

affect the rate of reaction.

[8 marks]

(c) Knowledge about the factors that affect the rate of reaction is very useful in

human life.

State two activities at home and explain how the knowledge about the factors

that affect the rate of reaction is applied in the activities mentioned.

[8 marks]



SULIT 4541/3


SULIT

1

Untuk Kegunaan Pemeriksa

Soalan Markah

Penuh

Markah

Diperoleh

1 18

2 15

3 17

JUMLAH 50

Nama : ... Kelas : ...

SEKTOR SEKOLAH BERASRAMA PENUH


_______________________________________________

PEPERIKSAAN PERCUBAAN SPM

2007

KIMIA

KERTAS 3

Satu jam Tiga Puluh Minit

JANGAN BUKA KERTAS SOALAN INI SEHINGGA DIBERITAHU

1. Tuliskan nama dan tingkatan pada ruang yang disediakan.

2. Calon dikehendaki membaca maklumat di halaman 2.


4541/3

Kimia

Kertas 3

Ogos

2007

1 Jam


SULIT 4541/3


SULIT

2

INFORMATION FOR CANDIDATES

1. This question paper consists of three questions. Answer all questions.

2. Write your answers for Question 1 and Question 2 in the spaces provided in the question

paper.

3. Write your answer for Question 3 on the lined pages at the end of the question paper in

detail.

4. Show your working. It may help you to get marks.

5. If you wish to cancel any answer, neatly cross out the answer.

6. The diagrams in the questions are not drawn to scale unless stated.

7. Marks allocated for each question or part question are shown in brackets.

8. The time suggested to answer Question 1 and Question 2 is 45 minutes and Question 3 is

45 minutes.

9. You may use a non-programmable scientific calculator.

10. Hand in this question paper at the end of the examination.

Marks awarded:

Mark Description

3 Excellent : The best response

2 Satisfactory : An average response

1 Weak : An inaccurate response

0 No response or wrong response

SULIT 4541/3


SULIT

3

Answer all questions

The time suggested to answer Question 1 and Question 2 is 45 minutes.

1. An experiment was carried out to investigate the effect of the size of the marble chips on

the rate of reaction. A burette was filled with water and inverted in a basin containing

water. The initial burette reading was recorded.

5.0 g of large marble chips were placed in a conical flask. 50 cm3 of 0.1 mol dm

-3

hydrochloric acid, HCl was added into a conical flask. The conical flask was closed with

a stopper fitted with a delivery tube directed to the burette and the stop-watch was started

simultaneously. The burette reading was recorded at 30-seconds intervals.

Experiment was repeated by using 5.0 g of small marble chips.

Diagrams below show the burette readings for the experiment between large marble chips

with hydrochloric acid.

(a) Record the volume of carbon dioxide gas in the spaces provided

Burette reading

cm3 at 0 min

50

49

48

Burette reading

cm3 at min

41

40

39

Burette reading

cm3 at 1 min

32

31

30

Burette reading

cm3 at 2 min 6

20

19

18

Burette reading

cm3 at 1 min

25

24

23

Burette reading

cm3 at 2 min

16

15

14

SULIT 4541/3


SULIT

4

[3 marks]

(b) Construct a table showing the changes of time, burette readings and volumes of

carbon dioxide gas liberated for the experiment.

[3 marks]

Burette reading

cm3 at 3 min 6

12

11

10

Burette reading

cm3 at 4 min

9

8

7

Burette reading

cm3 at 4 min

9

8

7

Burette reading

cm3 at 5 min

9

8

7

Burette reading

cm3 at 3 min 6

10

9

8

SULIT 4541/3


SULIT

5

(c) Table 1 shows the volume of carbon dioxide gas liberated when the experiment

was repeated by using 5.0 g of small marble chips.

Time /min

0 1 1 2 2 3 3 4

Volume of

carbon dioxide /

cm3

0.00 20.00 29.00 35.00 38.00 40.00 41.50 41.50 41.50

TABLE 1

Based on the data in (b) and Table 1, draw the graphs volume of carbon dioxide

gas liberated against time for both experiments on the same axes.

[3 marks]

(d) State the relationship between the size of marble chips and the rate of reaction?

........

[3 marks]

(e) Meat which is cut into small pieces takes a shorter time to cook compared to meat

that is cut into big pieces. Explain why?

[3 marks]

SULIT 4541/3


SULIT

6

SULIT 4541/3


SULIT

7

(e) Complete the table below based on the experiment.

Name of variables Action to be taken

(i) Manipulated variable

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

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

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

(i) The way to manipulate variable

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

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

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

(ii) Responding variable

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

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

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

(ii) What to observe in the

responding variable

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

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

(iii) Fixed variable

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

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

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

(iii) The way to maintain the fixed

Variable

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

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

[3 marks]

2 Diagram 2 shows the set-up of apparatus for an experiment to construct the

electrochemical series by measuring the potential difference of a few pairs of

copper and metal M in a simple voltaic cell using 1.0 mol dm-3

copper(II) sulphate

solution as an electrolyte.

DIAGRAM 2

Copper(II) sulphate

solution

Copper Metal M

SULIT 4541/3


SULIT

8

The result gained is shown in the table 2

Cell Metal pairs

Cu / M Voltage cell / V Negative terminal

I Cu / Fe 0.8 Iron, Fe

II Cu / Al 2.1 Aluminium, Al

III Cu / Mg 2.7 Magnesium, Mg

IV Cu / Zn 1.1 Zinc, Zn

V Cu / Cu 0.0 Copper, Cu

TABLE 2

(a) State a hypothesis of the experiment.

[3 marks]

(b) Based on Table 2, arrange all the metals according to descending order of

electropositivity.

[3 marks]

(c) What is the inference that can be made from voltage cell V.

........

[3 marks]

SULIT 4541/3


SULIT

9

(d) The diagram below shows simple voltaic cell IV before and after an experiment.

What can you observed in cell IV?

........

[3 marks]

(e) Predict the voltage cell if zinc and aluminium are used to construct

electrochemical series.

[3 marks]

Copper Zinc

Copper(II) sulphate

Solution (blue colour)

Copper Zinc

Copper(II) sulphate

Solution (light blue)

Before experiment

After experiment

SULIT 4541/3


SULIT

10

3

You are given the iron nails, magnesium ribbon, zinc strip, copper strip and tin strip.

Referring to the situation above, plan a laboratory experiment to investigate the effect of

other metals on the rusting of iron.

Your planning should include the following aspects:

(a) Statement of the problem (b) All variables (c) Statement of the hypothesis (d) List of materials and apparatus (e) Procedure of the experiment (f) Tabulation of data

[17 marks]


A more electropositive metal acts as a sacrificial metal which

corrodes itself to protect iron from rusting


SULIT 4541/3


SULIT

11

SPACE FOR YOUR ANSWER

Section: Question No.: .

SULIT 4541/3


SULIT

12

SPACE FOR YOUR ANSWER

Section: Question No.: .

SULIT 4541/1/2/3

4541/1

Kimia

Kertas 1

Ogos

2007

BAHAGIAN SEKOLAH


______________________________________________


KIMIA

Peraturan pemarkahan Kertas 1, 2 dan 3


2

Peraturan pemarkahan ini mengandungi halaman bercetak.

Kertas 1

1 A 21 B 41 A salah

Bbetul

2 B 22 D 42 A

3 A 23 D 43 C

4 B 24 C 44 B

5 B 25 B 45 B

6 C 26 C 46 B

7 D 27 D 47 B

8 A 28 A 48 A

9 Bsalah Dbetul 29 D 49 C

10 C 30 A 50 B

11 B 31 B

12 A 32 C

13 A 33 C

14 A 34 B

15 A 35 D

16 D 36 A

17 D 37 A

18 D 38 C

19 B 39 A

20 C 40 C


3

Kertas 2-Bahagian A

No. Rubric Mark

1

(a)

(b)

(c)

(d)

(e)

P: liquid

S: solid

1. Particles of Q held together by weak intermolecular forces 2. A small/less amount of heat energy is required to overcome

Diagram

1. label 2. functional apparatus

1. label of axis 2. shape of graph

1

1

1

1

1

1

1

1

19

2

(a)(i)

(ii)

(b)

(c)

(d)

(e)(i)

2.8.3 // 2,8,3 reject 2: 8: 3

F+3

// F3+

A,D,C,B,G,F,E

Atom A has a stable/duplet electron arrangement/2 valance electron

octet - reject

1. Size of atom D is smaller than G // G is bigger 2. Strength of the nucleus of atom D to attract electron increase

Ionic/ ionic compound

reject ionic bond

1

1

1

1

1

1

1

Time ( min)

Temperature / oC


4

(e)(ii)

(e) (iii)

1. Number of shells and electrons 2. Charge

- has high melting point and boiling point - conduct electricity in molten state or aqueous solution

reject can conduct electricity - soluble in water - insoluble in organic solvent

(Any one)

1

1

1...10

3

(a)

(b) (i)

(ii)

(iii)

(iv)

(c) (i)

(ii)

(iii)

(iv)

(d)

H+

, Cu

+2

Copper/cathode electrode becomes thicker//brown solid is deposited

Cu+2

+ 2e Cu Copper // metal/ electrode [reject copper ion// copper solution]

Oxygen gas [ reject water]

(from zinc plate to copper plate)

Oxidation

0 to +2 //0 +2 Increases / deflect more / higher

Zn + Cu+2

Cu + Zn+2

1

1

1

1

1

1

1

1

1

1...10

4

(a)

(b) (i)

(ii)

(c) (i)

Boron oxide

Tin

1. The presence of tin atoms of different size from the atoms of copper distrupts the orderly arrangements of copper atoms

2. This prevents the layers of atoms from sliding over one another easily

H Cl

| |

C == C

| |

H H

1

1

1

1

1

-

D

-

D E

x x x

x x x

2+

x x x x

x x

5

(ii)

(d)

(e) (i)

(ii)

Does not corrode / rust

Reinforced concrete

2NH3 + H2SO4 (NH4)2SO4//

2NH4OH + H2SO4 (NH4)2SO4 + 2H2O

% N in CO(NH2)2 = %67.46%10060

)14(2

% N in (NH4)2SO4 = %21.21100132

)14(2

Urea has higher percentage of nitrogen so it is more suitable for

the growth of plants

1

1

1

1

1

111

5

(a)

(b)(i)

(ii)

(c)(i)

(ii)

(d)(i)

(ii)

J: alkene

K: alcohol

Butan-2-ol

Hydration/addition of steam [reject dehydration / hydrogenation]

Orange to green

C3H7COOH

C4H8 + 6O2 4CO2 + 4H2O

No of mole C4H8 = )1(8)12(4

6.5

= 56

6.5

= 0.1

1 mole of C4H8 4 mole CO2

0.1 mole of C4H8 0.4 mole CO2

Volume of CO2 = 0.4(24)

= 9.6 dm3 / 9600 cm

3

1

1

1

1

1

1

1

1

1

110

6

(a)

(b)(i)

Reduce heat released to the surrounding/ to prevent heat lose

Heat change = 200 x 4.2 x 13

= 10920 J

1

1

6

(b)(ii)

(c)

(d)

(e)(i)

(ii)

Mole of H+/OH

-/water = 100 x 2.0 // 0.2 mol

1000

Heat of displacement = - 10920 J // -54.6 kJmol-1

0.2 mol

1. Label the energy axis & correct energy level of the reactants and product

2. Correct chemical equation// ionic equation

Heat released/ produced when 1 mol of water is formed

decreases / less / lower

1. Ethanoic acid is a weak acid 2. Some of the heat given out during the neutralization is used to

ionize/dissociate the ethanoic acid // absorb back

1

1

1

1

1

1

1

110

H+ + OH

-

H2O

Energy

7

Essay

No. Rubric Mark

7

(a)

1. pH value of ethanoic acid is higher than nitric acid 2. ethanoic acid is a weak acid; nitric acid is a strong acid 3. ethanoic acid ionises partially in water to produce lower

concentration of hydrogen ion

4. nitric acid ionises completely in water to produce higher concentration of hydrogen ion

1

1

1

14

(b)

1. ammonia exist as molecule in chloroform 2. there are no hydroxide ions present; the solution is not alkaline 3. when ammonia ionises partially in water to produce hydroxide ion

4. NH3 + H2O NH4+ + OH

-

5. the presence of OH- ions makes the solution alkali

1

1

1

1

15

(c)

1. Pour [20-100]cm3 of zinc nitrate solution [0.1-1.0]mol dm-3 into a beaker

2. Add [20-100]cm3 of sodium carbonate solution [0.1-1.0]mol dm-3 3. Stir and filter the mixture 4. Pour [20-100]cm3 dilute/[0.1-1.0]mol dm-3 sulphuric acid into a

beaker

5. Add the residue/precipitate into the acid until in excess 6. Stir and filter the mixture 7. Heat the filterate until saturated/1/3 of original volume 8. Cool the saturated solution 9. Filter and dry the crystal

10. Zn(NO3)2 + Na2CO3 ZnCO3 + 2NaNO3

11. ZnCO3 + H2SO4 ZnSO4 + H2O + CO2

1

1

1

1

1

1

1

1

1

1

1...11

20


8

No. Rubric Mark

8

(a)

Formula that shows the simplest ratio of the number of atoms for

each element in the compound.

11

(b)

Empirical formula : CH

RMM of (CH)n = 78

[ 12 + 1]n = 78

13 n = 78

n = 6

Molecular formula : C6H6

Element C H

Mass (%) 92.3 7.7

Number of

moles 12

3.92 = 7.7

1

7.7 = 7.7

Ratio of moles 1 1

1

1

1

1

15

(c)

Procedure:

1. Clean magnesium ribbon with sand paper 2. Weigh crucible and its lid 3. Put magnesium ribbon into the crucible and weigh the crucible

with its lid

4. Heat strongly the crucible without its lid 5. Cover the crucible when the magnesium starts to burn and

lift/raise the lid a little at intervals

6. Remove the lid when the magnesium burnt completely 7. Heat strongly the crucible for a few minutes 8. Cool and weigh the crucible with its lid and the content 9. Repeat the processes of heating, cooling and weighing until a

constant mass is obtained

10. Record all the mass

Results:

Mass/g

Crucible + lid x

Crucible + lid + magnesium y

Crucible + lid + magnesium oxide z

1

1

1

1

1

1

1

1

1

1

1

9

Calculatio

ns:

Empirical formula: MgaOb / MgO

Element Mg O

Mass (g) y-x z-y

Number of moles 24

xy

16

yz

Simplest ratio of moles a b

1

1

1...14

20

No. Rubric Mark

9

(a)

1. Oxidation - increase in oxidation number 2. Reduction decrease in oxidation number

1

12

(b)(i)

1. Fe+2 Fe+3 + e

2. Br2 + 2e 2Br

3. Iron(II) ions lose electrons to become iron(III) ions. Iron(II) ions are oxidised

4. Bromine molecules gain electrons to form bromide ions. Bromine molecules are reduced

(a: any suitable reducing agent)

1. Fe+3 + e Fe+2

2. Zn Zn+2 + 2e 3. Iron(III) ions gain electrons to become iron(II) ions. Iron(III)

ions are reduced

4. Zinc atoms lose electrons to form zinc ions. Zinc atoms are oxidised

(a: any suitable reducing agent)

1

1

1

1

1

1

1

18

10

(c)

Diagram:

1. label 2. functional apparatus

Procedure:

1. Pour dilute sulphuric acid into a U-tube 2. Using a dropper, add iron(II) sulphate solution at one side 3. and acidified potassium manganate(VII) solution at another side 4. Place carbon electrode in each side of the U-tube 5. Connect the electrodes to a galvanometer by using connecting

wires//Complete the external circuit

6. Record any change that can be observed after a few minutes

Observations:

The green colour of iron(II) solution turns to brown

The purple colour of acidified potassium manganate(VII) solution is

decolourised/change to colourless

(a: any suitable cell)

1

1

1

1

1

1

1

1

1

110

20

No. Rubric Mark

10 (a) (i)

Catalyst is a substance that changes the rate of a chemical reaction.

1

(a) (ii)

- does not change the amount of product formed.

- unchanged chemically at the end of reaction.

- the amount of catalyst is the same before and after the reaction.

- it is specific for a reaction.

- only small amount is needed to catalyze a reaction.

- less effective when there are impurerities.

- most of the catalyst are transition metals or their compound.

(Any two)

1

12

(a) (iii)

- Haber process: iron filling

- Contact process: vanadium(V) oxide

- Ostwald process: platinum

11

11

(Any one)

(b)

1 Size of reactant

- size of reactant decrease, total surface area exsposed for collision

between the particles reactants increase

- frequency of collision between particles increase

- frequency of affective collision increase

rate of reaction increase

2 Concentration of reactant

- concentration of a solution increase, number of particles per unit

volume increase




3 Temperature of reaction

- temperature of reactants increase, kinetic energy of particles

reactants increase




(Any two)

1

1

1

14

1

1

1

14

1

1

1

14

(c)

1 Cooking of solid food

- solid food cut into small piece

- total surface area exsposed to heat increase

- food cook faster

2 Cooking of food in a pressure cooker

- high pressure raises the boiling point of water.

- cooking is carried out at a temperature higher than 100 o C.

- food cook faster.

3 Storing of food in a refrigerator

- temperature in refrigerator is lower

- microorganisms inactive

- slow down rate of food decaying

(Any two)

(a: any suitable answer than above)

1

1

1

14

1

1

1

14

1

1

1

14

20

12

PAPER 3

1 ( a )

Score Rubric

3 [ Able to state all 11 readings correctly ]

2 decimal places

Unit cm3 Suggested answer

49.60, 40.10, 31.50, 24.10, 19.50, 15.10, 11.50, 9.60, 8.10, 8.10. 8.10

2 [ Able to state any 8 readings correctly ]

1 [ Able to state any 4 readings correctly ]


1 (b)

S

core

Rubric

3

[Able to design a table and record the time, buret reading and volume of gas liberated]

1. Time /minute 2. Buret reading /cm3 3. Volume of gas liberated

Suggested answer:

Time

/min

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

Buret

reading

/cm3

49.60 40.10 31.50 24.10 19.50 15.10 11.50 9.60 8.10 8.10 8.10

Volume

of gas /

cm3

0.00 9.50 18.10 25.50 30.10 34.50 38.10 40.00 41.50 41.50 41.50

2

[Able to design a table and record two of the 3 items (time, buret reading and volume of

gas liberated] // [Able to design table without unit]

1

[Able to give idea on table ]

Suggest answer: 2 rows x 11 columns


13

1 (c)

Score Rubric

3 [ Able to draw 2 graphs of volume of carbon dioxide gas liberated against time

for both experiments on the same axes with all the 4 items below correctly ]

(i) suitable scale used

(ii) axes labelled correctly

(iii) all points plotted correctly

(iv) smooth curve of graphs

2 [Able to draw the graphs of volume of carbon dioxide gas liberated against

time for both experiments on the same axes with at least 3 items correctly] //

[Able to draw one of the graphs volume of carbon dioxide gas liberated against

time with at least 4 items abovebelow correctly]

1 [ Able to manipulate two items correctly ]


1 ( d )

Score Rubric

3 [Able to deduce the relationship between the size of marble chips and the rate of

reaction correctly].

Suggested answer:

Small pieces of marble chips have a large total surface area than that a large

pieces of marble chips of the same mass, course the time taken for reaction

more faster / rate of reaction more higher

2 [Able to give incomplete relationship]

Suggested answer:

Small pieces of marble chips have a large total surface area time taken for

reaction more faster / rate of reaction more higher

1 [Able to give an idea ]

Suggested answer:

Small pieces of marble chips have a large total surface area // time taken for

reaction more faster when size of reactant smaller // rate of reaction depend on

the size of reactant


14

1 (e)

Score Rubric

3 [ Able to state three variables and the way to control them correctly ]

Example :

Manipulated variable :

Total suface area of marble

Replace large marble chips with

small small marble chips

Responding variable :

Rate of reaction // time

Measure the volume of gas collected

at half-minute interval

Fixed variable :

Mass of marble, volume of

hydrochloric acid, temperature

Use the same mass/5.0 g marble,

same volume/50 cm3 and

concentration/ 0.1 mol dm-3

hydrochloric acid, same tepperature

in each of the experiment

2

[ Able to state any pair of variable and action correctly ]

1 [ Able to state any variable and any action correctly // any two variables

correctly // any two action correctly]


1 (f)

Score Rubric

3 [Able to state relationship small pieces of meat and time to cook correctly]

Suggested answer

Smaller pieces of meat has bigger total surface area

The larger surface area provides a larger area for absorbtion heat

Increased obsorption of heat shorten cooking time// The rate of reaction increases

2 [Able to give incomplete relationship ]

Suggested answer

[state the any two items above]

1 [Able to give an idea // state any one items above]


15

2 (a)

Score Rubric

3 [Able to give the hypothesis accurately]

Suggested answer :

The further the metal is from copper in the electrochemical series, the greater

is their potential different/ voltage reading. //

The further apart the metal is in the electrochemical series, the greater the

potential different/ voltage reading.

2 [Able to give the hypothesis almost accurately]

Suggested answer :

The further the metal is from copper in the reactivities series, the greater is

their potential different/ voltage reading. //

The further apart the metal is in the reactivities series, the greater the potential

different/ voltage reading.

1 [Able to state an idea of hypothesis]

Suggested answer :

The position of metal influence the different potential/ voltage reading.

Type of metal influence the different potential/ voltage reading.


2 (b)

Score Rubric

3 [Able to arrange all the 5 metals according to descending order of

electropositivity correctly]

Suggested answer:

Magnesium, Aluminium, Zinc, Iron, Copper

[a: formula]

2 [Able to arrange all the 4 metals but according to increasing order of


Example:

Mg, Al, Fe, Cu, Zn // Al, Zn, Fe, Cu, Mg // Al, Zn, Mg, Fe, Cu

1 [Able to arrange all the 5 metals but according to ascending order of


Example ;

Cu, Fe, Zn, Al, Mg

16


2 (c)

Score Rubric

3 [Able to state inference correctly].

Suggested answer

Electrical energy is not produced

No movement of electron because the same type of metal are used as electrodes in a voltaic cell

2 [Able to state inference not completely].

Suggested answer

Electrical energy is not produced // no movement of electron because the same

type of metal are used as electrodes in a voltaic cell

1 [Able to state an idea]

Example

No electric/electron/potential difference


2 (d)

Score Rubric

3 [Able to state three observations correctly]

Suggested answer:

1 Zinc dissolved // becomes thinner

2 Copper becomes thicker // brown solid deposited

3 Blue solution becomes light blue /fading in colour

2 [Able to state two observation correctly]

1 [Able to state one observation/idea about observation of the cell]

0 No response given or wrong response

17

2 (e)

Score Rubric

3 [Able to predict correctly] Answer: 1.0 V

2 [Able to predict almost correctly]

Example:

1.0

1 [Able to state an idea to arrange the metals]

Example:

Reading is higher than 0.5 / lower than 1.5


Essay

3 (a) - Statement of the problem

Score Rubric

3

[ Able to give the statement of problem correctly ]

Example :

How the effect on rusting when iron is in contact with another metals?

2

[ Able to give the statement of problem incorrectly ]

Example :

To investigate the effect of other metals on the rusting of iron

1

[ Able to state an idea the statement of problem]

Example :

To study the rusting of iron

0 [ No response or wrong response]

18

3 (b) - variables

Score Rubric

3

[ Able to state All variables correctly ]

Suggested answer :

Manipulated variable : Different types of metals// Different metals

Responding variable : Rate of rusting // Rusting of iron

Constant variable : Iron nails/temperature

2

[ Able to state any two variables correctly ]

1

[ Able to state any one variables correctly ]

0 [ No response or wrong response]

3 (c) - hypothesis

Score Rubric

3 [Able to give the hypothesis accurately]

Suggested answer :

When a more electropositive metal is in contact with iron, the metal inhabits

rusting // When a less electropositive metal is in contact with iron, the metal

speed up rusting // Iron rusts faster when in contact with metal less

electropositive

2 [Able to give the hypothesis almost accurately]

Suggested answer :

When a more reactive metal is in contact with iron, the metal inhabits rusting

1 [Able to state an idea of hypothesis]

Suggested answer :

When a less electropositive metal is in contact with iron, the metal inhabits

rusting


19

3 (d) - Apparatus and materials

Score Rubric

3

[ Able to give the list of the apparatus and substances correctly and

completely]

Suggested answer :

Apparatus : Five test tubes, test tube rack

Materials : sand paper, five iron nails, magnesium strip, zinc strip, tin strip,

copper strip, hot agar-agar/jelly solution mixed with potassium

hexacyanoferrate(III) solution and phenolphthalein indicator

2

[ Able to give the list of the apparatus and substances correctly and but not

completely]

Example :

List of apparatus and materials

Test tube, iron nail, magnesium,zinc, tin,copper,water, potassium

hexacyanoferrate(III) / phenolphthalein indicator

1

[ Able to give an idea about the list of the apparatus and materials correctly]

Example :

Any one apparatus and two materials

0 [No response or wrong response]

3 (e) - Procedure of the experiment

Score Rubric

3

2007 sbp with answer

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