kimia 123 dan skema

4541/1 [Lihat sebelahSULIT

SULIT 4541/1

4541/1ChemistryPeper 1Oktober 2009

1 1/4 jam

PEJABAT PELAJARAN DAERAH MELAKA TENGAH_______________________________________________________

PROGRAM LONJAKAN SAUJANA SPM 2009

CHEMISTRY

Paper 1

Satu jam lima belas minit

JANGAN BUKA KERTAS SOALAN INI SEHINGGA DIBERITAHU

1. Kertas soalan ini mengandungi 50 soalan

2. Jawab semua soalan

3. Jawab dengan menghitamkan ruangan yang betul pada kertas jawapan

4. Hitamkan satu ruangan sahaja bagi setiap soalan

5. Rajah tidak dilukis mengikut skala kecuali dinyatakan

6. Anda dibenarkan menggunakan kalkulator saintifik yang tidak boleh diprogramkan

Kertas soalan ini mengandungi 20 halaman bercetak.

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2

1 The figure below shows the set-up of the apparatus to study Process I

W

A

B

C

D

2 W

A

B

C

D

1 [Lihat sebelahSULIT

hat is Process I ?

Condensation

Evaporation

Diffusion

Sublimation

hat is the definition of a mole ?

The volume occupied by 6.02 X 1023 particles

The atomic mass of a substance which consists of 6.02 X 1023 atoms

The molecular mass of a substance which consists of 6.02 X 1023 molecules

The quantity of substance which has the same number of particles as the

number of atoms in 12 g of Carbon-12

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3

3 The figure below shows the heating curve for substance N

Which of the following gives the correct states of substance N at X, Y and Z asshown in the graph?

A

B

C

D

X Y Z

solid liquid gas

solid solid and liquid gas

solid solid and liquid liquid

liquid liquid and gas solid

4 Which of these is the correct sequence of scientific method of investigation ?

A

B

C

D

Observation → inference → determining the variables → doing experiment

Analysing data → collecting data → making conclusion → identifying problem

Hypothesis → doing the experiment → conclusion → inference

Doing the experiment → hypothesis → analysing data → inference

TemperatureoC

Z

Y

X

Time/s

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4

5 When steam condenses, the particles

A

B

C

D

become smaller size

lose energy to their surroundings

move futher apart

vibrate about fixed positions

6 The figure below shows an electron arrangement of Y2+

How many

A

B

C

D

Proto

8

12

12

8

7 What can w

A

B

C

D

An ato

An ato

Helium

Helium

protons and electrons does an atom of Y contain ?

n Electron

8

10

12

10

e deduce from the symbol

m of helium contains two e

m of helium has two proton

has a proton number of 4

occurs as a diatomic mole

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?

lectrons

s and four neutrons in its nucleus

cule

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8 The relative formula mass of ammonium phosphate, (NH4)3PO4 is[ Relative atomic mass of H=1, N=14, O=16 and P=31]

A

B

C

D

133

141

149

159

9 Rouge is a pigment which contains 2.8 g of iron combined with 1.2 g of oxygen.What is the chemical formula of rouge ?[ Relative atomic mass of Fe=56 and O=16 ]

A

B

C

D

FeO

Fe2O3

Fe3O2

Fe3O4

10 A metal X can exist as X2+ and X3+ ions. The possible formulae for its sulphateswould be

I XSO4

II X2SO4

III X2(SO4)3

IV X3(SO4)2

A

B

C

D

I and II only

I and III only

II and III only

II, III and IV only

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6

11 Which of the following electron arrangements is found in an atom of a noble gas?

A

B

C

D

1

2.1

2.8

2.8.2

12 The following table shows the proton number and nucleon number of atom X

Which of th

A

B

C

D

Group

1

17

1

17

13 The table bElements.

Which of th

A

B

C

D

The a

Atom

The n

Atom

Proton number 9

e following shows the position of X in the Periodic Table of elements?

Period

4

2

1

4

elow shows the position of 2 elements, P and Q, in the Periodic Table of

e

to

s o

um

s o

Nucleon number 19

Elements Group PeriodP 1 3

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following is true about elements P and Q ?

ms of P are smaller than the atoms of Q

f P have stronger attraction for other electrons

ber of positive charges in the nucleus of P is less than Q

f Q have a higher tendency than P to release electrons

Q 17 3

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14 The chemical symbol of an element T is as shown :

What would be the electron arrangement of the ion formed by an atom of T ?

A

B

C

D

2.8

2.8.2

2.8.8

2.8.8.8

15 The electron arrangement of atom X = 2.8.7. What is the formula of the ion formedfrom X ?

A

B

C

D

X-

X+

X7-

X7+

16 The electron arrangements of 2 atoms X and Y are as shown :

Whic

A

B

C

D

12

X

h of the following is true wh

X receives electrons

Y receives electrons

The compound formed has

The compound formed is m

24

T

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Y

en X react with Y?

a formula of XY2

ade up of molecules

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17 The proton numbers of a few elements are as shown :

With the atoms oelectrons?I HII NaIII MgIV SA

B

C

D

I only

II only

II and III on

I and IV on

18 It is discovered thcan you make ab

A

B

C

D

It is not a c

The compo

The compo

The interm

Element Proton NumberH 1Na 11Mg 12

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S 16

f which element would chlorine atoms combine by sharing

ly

ly

at a compound with formula WZ dissolves in water. What inferenceout the compound ?

ovalent compound

und ionizes in water

und will not dissolve in an organic solvent

olecular forces between the particles are very weak

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19 The following diagram shows the apparatus set up for an elelctrolysis.

Which of the f

A

B

C

D

Ammoni

Sodium C

Ethanoic

Ether

20 An experimenX, Y and Z inresults are as s

Which of the fdescending ord

A

B

C

D

X, Y, Z

Y, X, Z

Z, X, Y

Z, Y, X

X +X +Y +Z +

E

ollowing cannot be E ?

um hydroxide

hloride

acid

t has been carried out to determine the relative position of three metalsthe electrochemical series by using the displacement reaction. Thehown :

Mixture Resultssolution of Y Y depositedsolution of Z No reactionsolution of Z No reaction

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ollowing shows the correct relative position of X, Y and Z iner of tendency to release electrons?

solution of Y Y deposited

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21 Which of the following compounds is a soluble base?

A

B

C

D

Aluminium oxide

Copper(II) oxide

Iron(III) oxide

Sodium oxide

22 The pH scale below shows the position of five aqueous solutions P, Q, R, S and T, ofequal concentration.

P Q R S T

1 7 14pH Scale

What could the aqueous solutions be ?

A

B

C

D

Ethanoic sulphuric ammonia sodium sodium

acid acid aqueous chloride hydroxide

P Q R S T

Q P S R T

Q P T S R

S T Q R P

23 What is the concentration of hydrogen ions in 0.05 mol dm-3 sulphuric acid?

A

B

C

D

0.025 mol dm-3

0.050 mol dm-3

0.100 mol dm-3

0.250 mol dm-3

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24 Which of the following equations best represents the actual reaction betweenhydrochloric acid and sodium hydroxide solution?

A

B

C

D

H+ + OH- H2O

H2 + ½ O2 H2O

2H+ + O 2- H2O

Na+ + Cl- NaCl

25 The neutralization reaction between nitric acid and barium hydroxide solution isshown in the equation below

2HNO3 + Ba(OH)2 Ba(NO3)2 + 2H2O

10.0 cm3 of 0.1 mol dm-3 barium hydroxide solution was titrated with 0.1mol dm-3

of nitric acid . What is the volume of the nitric acid?

A

B

C

D

10 cm3

20 cm3

30 cm3

40 cm3

26 Air polluted by sulphur dioxide was passed through the apparatus shown in thediagram below.

Which of the follosulphur dioxide?

A

B

C

D

acidified pot

aqueous iron

aqueous pota

limewater

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wing solutions could be used as Z to show the presence of

assium manganate(VII)

(II) sulphate

ssium iodide

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27 The following scheme shows four stages in the conversion of sulphur to sulphuricacid. In which stage is the catalyst used?

28 Which of the following mixtures of elements forms the most suitable alloy formanufacturing of racing bicycle which is light and firm?

A

B

C

D

copper and nickel

iron and carbon

stanum and copper

aluminium and copper

29 Which of the following pairs shows the correct monomer for making the respectivepolymer?

A

B

C

D

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30 The followings are the properties of glass. Which of the followings are true?

I low melting point.

II they are good insulators of heat.

III resistant to chemicals

IV hard but brittle

A

B

C

D

I and II only

III and IV only

I, III and IV only

II, III and IV only

31 Compound A is an organic compound. When heated strongly, which of the followinggases is released?

A

B

C

D

Oxygen

Hydrogen

Carbon dioxide

Ethane

32 The following chemical equations show two chemical reactions that took place.

Which of the following shows the correct reaction represented by X and Y ?

X CH2CHCH2CH3 +H2 CH3CH2CH2CH3

Y CH2CHCH2CH3 +H2O CH3CH(OH)CH2CH3

A

B

C

D

X Y

Hydration Hydrogenation

Hydrogenation Hydration

Substitution Dehydration

Oxidation Reduction

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33 Which of the following is the IUPAC name for the structural formula shown

below?

A

B

C

D

3-ethyl-4-methylheptane

4-methyl-2-ethylhexane

5-ethyl-3-methylheptane

2-ethyl-4-methylhexane

34 Which of the following is correct regarding the physical properties of pentene,C5H10?

A

B

C

D

Pentene is denser than hexene.

Pentene exists in the form of gas at room temperature

Complete combustion of pentene will produce 4 moles of carbon dioxide gas.

Pentene is insoluble in water but is soluble in organic solvent.

35 Which of the following best explains the statement below?

Combustion of hexene is sootier than that of hexane

A

B

C

D

Hexane molecule has more hydrogen atoms than hexene molecule.

The van der Waals’ forces between hexene molecules are stronger.

Percentage by mass of carbon in hexene molecule is higher than that in hexane

molecule.

The size of hexene molecule is larger.

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36 In a reaction temperature will increase the rate of reaction because it will

A

B

C

D

lower the activation energy of the rection

increase the energy of particles involved in the reaction

decrease the effective collision of particles involved

increase the rate of collision among the particles

37 The table shows the volume of oxygen gas obtained at regular intervals for thedecomposition of hydrogen peroxide, H2O2

Time(min) Volume of oxygen gas (cm3)

0 0

1.0 5.5

2.0 10.0

3.0 14.0

4.0 17.5

5.0 20.0

The everage rate of decomposition of hydrogen peroxide from the second minute to

the fourth minute is

A

B

C

D

17.5 cm3 min-1

12.5 cm3 min-1

3.75 cm3 min-1

4.17 cm3 min-1

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16

38 The graph below shows the volume of gas produced against time for the reaction ofpotassium carbonate and hydrochloric acid

The gradient of the graph decreases with time because

A

B

C

D

catalyst is not used

temperature of reaction decreases

volume of mixure decreases

concentration of hydrochloric acid decreases

39 Which of the following will increase the frequency of collision?

I Use reactant with larger size

II Increase the concentration of reactant

III Increase the temperature of reaction

IV Remove the product of reaction

A

B

C

D

IV only

II and IV only

II and III only

I, III and IV only

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40 The equation below shows one of the reaction to produce hydrogen gas

2HCl + Zn ZnCl2 + H2

Which of the following would increase the rate of production of hydrogen gas?

A

B

C

D

Increase the time of reaction

Increase the volume of acid

Increase the size of granulated zinc

Increase the tempereture of the mixture

41 Which of the following chemicals can oxidise chloride ions to chlorine?

A

B

C

D

Potassium manganate (VII)

Iron(III) sulphate

Aqueous bromine

Potassium

42 Which of the following is an oxidising agent?

A

B

C

D

Hydrogen gas

Potassium manganate(VIl)

Potassium Iodide

Ammonia

43

Which ofabove s

A

B

C

D

Psych

Horm

Analg

Antib

A patient claims that other people are reading his mind

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the following types of medicine is most appropriate in treating theymptoms

otherapeutic medicine

ones

esic

iotics

and controlling his thoughts

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18

44 A series of experiment was carried out to investigate the reactivity ofmetals X, Y and Z. The following results were obtained.

Mixture ResultX+ oxide of Y No reaction.

Y+ oxide of Z Reaction occurred.

X + oxide of Z Reaction occurred.

Which of the following is the correct sequence of the metals in descending order ofreactivity?

A

B

C

D

X, Y, Z

Z, X, Y

Y, Z, X

Y, X, Z

45 The figure bellow shows the energy profile diagram for a reaction between X and Yto produce Z.

What is the heat of reaction?

A

B

C

D

E2 – E1

E1 – E2

E3 – E1

E3 – E2

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19

46 Which of the following is an exothermic reaction?

A

B

C

D

The heating of hydrated copper(II) sulphate

The heating of sodium thiosulphate

Dissolving ammonium chloride in water

Rusting process

47 The figure below shows the change in the heat of combustion of a few alcohols.

The increase in the heat of combustion of alcohols as shown is due to

ABCD

an increase in the sootiness of the alcohols when burntan increase in the reactivity of alcoholsan increase in the relative molecular massan increase in the number of carbon and hydrogen atoms per molecule ofalcohol

48 Which of the following pairs regarding traditional medicines and their uses iscorrect?

A

B

C

D

Traditional medicine UseEurycoma longifolia To relief asthmatic attack

Aloe vera To treat skin wounds

Garlic To treat stomach wind

Ginseng To treat malaria

Propanol ( C3H7OH )

Ethanol ( C2H5OH )

Methanol ( CH3OH )

Heat ofcombustionincreases

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20

Detergent is more effective for washing in hard water, but soap is very often used ineveryday life. The advantage of soap over detergent is that

soap is more effective for washing in acidic water compared to detergent

soap has a fragrant smell where as detergent has a pungent smell

soap is biodegradable where as many detergents are not

soap is cheaper than detergent.

50 Which of the following is one of the possible products formed when palm oil isboiled in concentrated sodium hydroxide solution ?

I Sodium chlorideII GlycerolIII Sodium palmitateIV Sodium stearate

A

B

C

D

II and III only

I, II and III only

II, III and IV only

I, II, III and IV

KERTAS SOALAN TAMAT

49

A

B

C

D

SULIT4541/2 NameChemistryPaper 2 FormOctober 20092 1/2 hours

PEJABAT PELAJARAN DAERAH MELAKA TENGAH

_______________________________________________________


CHEMISTRYPaper 2

Two hours and thirty minutes

DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE TOLD TO DO SO

1. This question paper consists of three sections: Section A,Section B and Section C.

2. Answer all questions in Section A. Write your answers forSection A in the spaces provided in the question paper.

3. Answer one question from Section B and one question fromSection C. Answers questions in Section B and Section C indetail. You may use equations, diagrams, tables, graphs andother suitable methods to explain your answer.

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

5. The diagrams in the questions are not drawn to scale unlessstated.

6. Marks allocated for each question or part question are shownin brackets.

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

8. Hand in your answer sheets at the end of the examination.

For Examiner’s use only

Section No. Marks

1

2

A 3

4

5

6

Total

B 7

8

Total

C 9

10

Total

Total marks

This question paper consists of 16 printed pages4541/2 [Lihat sebelah

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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/ ºC Boiling point/ ºCW -5 67X -105 -38Y 80 140Z 801 1413

TABLE 1

(a) What is the physical state of W and Z at room temperature?

W: ....................................................................................................................

Z : ....................................................................................................................[2 marks]

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

[1 mark]

(c) Explain why substance X 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 Y.

[2 marks]

(e) Sketch the graph of temperature against time for substance Y when it isheated from room temperature until it reaches a temperature of 100oC.

[2 marks]

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4

2 Table 2 shows the proton number of a few elements in Period 3.

Element Sodium Magnesium Aluminium Chlorine Argon

Proton number 11 12 13 17 18

TABLE 2

Based on Table 2, answer the following questions :

(a) Name two metals.

………………………………………………………………………………………[1 mark]

(b) Chlorine is in group 17 in the Periodic Table. What is another name for group17elements?

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

(c) Write the electron arrangement of aluminium atom.

………………………………………………………………………………………[1 mark]

(d) (i) Compare the atomic size of sodium and chlorine.

………………………………………………………………………………[1 mark]

(ii) Explain your answer in (d) (i).

………………………………………………………………………………

………………………………………………………………………………[2 marks]

(e) When sodium is burnt in chlorine, sodium chloride is formed.

(i) Write the chemical equation for the reaction.

………………………………………………………………………………[3 marks]

(ii) State one physical property of sodium chloride.

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

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3 Diagram 3 shows two types of cell.

(a) W

…

(b) (i

(

(

(

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5

Cell X Cell Y

DIAGRAM 3

rite the formula of all the ions present in the copper (II) sulphate solution.

………………………………………………………………………………[1 mark]

) State the observation at the cathode of cell X.

……………………………………………………………………………[1 mark]

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

……………………………………………………………………………[ 1 mark]

iii) State the energy change in cell X.

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

iv) Name the product formed at the anode if copper electrodes in cell X arereplaced by carbon electrodes.

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

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6

(c) Based on cell Y,(i) Show the direction of electrons flow through the circuit in cell Y

in Diagram 3.[1 mark]

(ii) State the redox process that occurs at the zinc plate.

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

(iii) State the change in oxidation number of zinc in this reaction.

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

(iv) What happens to the voltage of the cell if the copper plate is replaced withsilver plate?

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

(d ) Write an ionic equation for the overall reaction.

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

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7

4 (a) A bicycle is made up of various parts, as shown in Diagram 4.1

(i) The frame of the bicycle is made of steel. What elements does steel consist of ?

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

(ii) Draw the arrangement of atoms in steel.

[2 marks]

(iii) Steel is strong but is not suitable to be used for the wheel rim of a racing bicycle.Why?

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

Wheel rim

Frame

DIAGRAM 4

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8

(b) Diagram 4.2 shows parts of a car made up of manufactured substances in industry.

(i) The car seat is covered with polyvinyl chloride, PVC a synthetic polymer. Name themonomer of polyvinyl chloride.

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

(ii) Explain how the usage of a synthetic polymers like PVC can give rise toenviromental pollution problem.

…………………….…………………………………………………………………….

…………………….………………………………………………………………….....[2 marks]

(iii) The windscreen of the car is made of glass. There are four types of glass been used inour daily lives. Complete the table below with the types of glass and their uses.

Type of glass Uses

……………………………….

Laboratory glassware Lenses Telescope mirrors Optical fibres

……………………………….

Electrical bulb Mirrors Most kinds of glass container

………………………………. Finest tableware Art objects

Borosilicate glass

Cookware Laboratory glassware Automobile headlights Glass pipelines

[3 marks]

PVC seat cover

Glass windscreen

DIAGRAM 4.2

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45

5 Figure below shows the structural formulae of compounds J, K and L


9

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

Compound J : …………………………………………………………………

Compound K : …………………………………………………………………[ 2 marks ]

(b) In the figure given, circle the functional group of compound L .

[ 1 mark ]

(c) (i) Name the compound K

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

(ii) Another compound, M, is in the same homologous series as K. M has fivecarbon atom. Write the molecular formula for M.

…………………………………………………………………………………[ 1 mark ]

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10

(d) Draw the structural formula for another isomer of compound J. Name theisomer.

[ 2 marks ]

(e) When compound K is added into a test tube containing acidified potassiumdichromate(VI) solution and heated for a few minutes, compound L is form.

(i) State one observation for this experiment

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

(ii) Write a chemical equation for this reaction.

……………………………………………………………………………….[ 2 marks ]

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6 Figure 6 shows the set-up apparatus to investigate the reactions that take place in test tubesP and Q.

(a) State th

(i) in te

.....

(ii) in t

.....

(b) Write th

...........

(c) State w

..........

(d) Referin

(i) wh

....

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11

FIGURE 6

e observation for the reaction

st tube P

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

est tube Q

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

e ionic equation for the reaction in (a)(i)

.................................................................................................................................[ 2 marks ]

hat is meant by oxidation in terms of electron transfer.

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

g to the reaction that takes place in test tube P,

at is the change in the oxidation number of magnesium ?

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

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12

(ii) name the oxidizing agent

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

(e) Referring to the reaction that take place in test tube Q,

(i) state the type of reaction that bromine undergoes.

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

(ii) what is the oxidation number of bromine in bromine water

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

(iii) what is the function of bromine water ?

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

(iv) name another reagent that can replace bromine water

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

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Section B[20 marks]

Answer any one question.

7 (a) What is meant by empirical formula and molecular formula

[3 marks](b) Diagram 7.1 is the information of alkene X.

[ RelatBased on

(i)(ii)(iii)(iv)

(c) Table 7.2

Brom

Brom

ExplainWrite th

(d) Alken

(i)(ii)(iii)

A

Carbon, C 85.7 %Hydrogen, H 14.3 %

ive atomic mass: H = 1 ; C = 12 ]the information in Diagram 7.1 :

Calculate the empirical formula of alkene XDetermine the molecular formula of alkene XName the alkeneWrite the general formula for its homologous series

[8 marks]

shows the result of a test to differentiate between alkene X and alkane Y.

Procedure Observations

ine water is added to alkene X Brown colour is decolourised

ine water is added to alkane Y Brown colour remains

TABLE 7.2

why there is a difference in these observations.e chemical equations for the reactions that take place.

[5 marks]

e X can be converted to alkane Y through a reaction as shown below.

Relative molecular mass = 56

DIAGRAM 7.1

13

Name the reaction.What are the optimum conditions for theWrite the chemical equation for the reac

lkene X

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reaction occur.tion.

[4 marks]

Alkane Y

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14

8 (a) The table below shows the data obtained when 2.0 g of calcium carbonate granuleswere added to 20.0 cm3 of 0.1 mol dm-3 hydrochloric acid in a conical flask.

Time/s 0 60 120 180 240 300 360 420Volume of gas/cm3 0.0 5.0 9.5 13.0 16.5 18.5 19.0 19.0

(i) Based on table , draw a graph of volume of gas against time[4 marks]

(ii) From the graph, determine the average rate of reaction for the whole reaction the rate of reaction at 210 seconds

[4 marks]

(iii) Explain why potatoes fried in boiling oil cooks faster than potatoes boiled inboiling water.

[2 marks]

(iv) By using the collision theory, explain how temperature affects the rate ofreaction.

[4 marks]

(b) The table below shows three types of food additive and their functions

Type of foodadditive

Function

X To slow down or prevent the growth of microorganismsso that food can be kept for a longer period.

Y To prevent oxidation that causes rancid fats andfruits from turning brown

Z To improve and restore the taste of food

State the type of food additive X, Y and Z . State one example each.

[6 marks]

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Section C[20 marks]

Answer any one question.

9 (a) Define oxidation and reduction in terms of changes in oxidation number.[2 marks]

(b) Explain, in terms of electrons tranfer, the oxidation and reduction processes in thefollowing conversions :

(i) conversion of Fe2+ ions to Fe3+ ions

(ii) conversion of Fe3+ ions to Fe2+ ions

In your anwer, give a suitable example for each of the conversion, including thehalf equations

[8 marks](c)

Describelectron

[Lihat sebelahSULIT

15

e an experiment to prove the above statement by using transfer ofs at a distance. In your description, you are required to includea labelled diagram which shows the set up of apparatusthe procedure of the experimentthe observations at both the electrodes

[10 marks]

Electrical energy can be produced by redox reaction.

SULIT 4541/2


16

10. (a) A pupil carried out an experiment to investigate the chemical changes that occurto barium chloride as a result of reaction P. The result of the experiment is shown inDiagram 10

(i) The chemical equation for reaction P is as follows :

BaCl2 + Na2SO4 → BaSO4 + 2NaCl

Excess sodium sulphate is added to 50 cm3 of 0.5 mol dm-3 barium chloride.[ Given the molar mass of BaSO4 = 233 ]

Calculate the mass of barium sulphate formed.[3 marks]

(ii)Describe the experiment how to prepare the dry barium sulphate in the laboratory.

[7 marks]

(b) You are provided with barium chloride solution, sodium sulphate solution and othersuitable apparatus.Deccribe how you can determine the heat of precipitation of barium sulphate,BaSO4

in the laboratory . Your explanation should include data tabulation and calculation.

[10 marks]

END OF QUESTION PAPER

DIAGRAM 10

Barium chloride solution

Sodium sulphate solution

Sodium chloride solution

Barium sulphate precipitate

Reaction P

SULIT 4541/3

4541/3 [ Lihat sebelahSULIT

SULIT4541/2 NameChemistryPaper 3 FormOctober 20091 1/2 hours



CHEMISTRYPaper 3

One hour and thirty minutes

DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE TOLD TO DO SO

1. Tuliskan nama dan tingkatan padaruang yang disediakan.

2. Calon hendaklah membaca arahan padahalaman 2 dan 3.

Untuk kegunaan pemeriksa sahaja

SoalanMarkahPenuh

Markahdiperolehi

1 18

2 15

3 17

Jumlah 50

This question paper consists of 11 printed pages

SULIT 4541/3


2

INFORMATION FOR CANDIDATES

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

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

3. You may use equations, diagrams, tables, graph and other suitable methods to explain youranswer.

4. Show your working, it may help you to get marks.

5. If you wish to change your answer, neatly cross out the answer that you have done. Thenwrite down the new 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 each of the questions is 30 minutes.

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

10. Hand in your answer sheets 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


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 chipson the rate of reaction. A burette was filled with water and inverted over a basin ofwater. 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 closedwith a stopper fitted with a delivery tube directed to the burette and the stop-watch wasstarted simultaneously. The burette reading was recorded at 30-seconds intervals.

The above xperiment was repeated by using 5.0 g of small marble chips.

Diagrams on the next page shows the burette readings for the reaction between largemarble chips and hydrochloric acid.

SULIT 4541/3


4

(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 ½ min

41

40

39


32

31

30

Burette reading……… cm3 at 2 min6

20

19

18

Burette reading……… cm3 at 1½ min

25

24

23


16

15

14

Burette reading……… cm3 at 3 min6

12

11

10


9

8

7

Burette reading……… cm3 at 3½ min6

10

9

8

SULIT 4541/3


5

[3 marks]

(b) Construct a table to show the time, burette readings and volumes of carbondioxide gas liberated in the experiment.

[3 marks]

(c) Table 1 shows the volume of carbon dioxide gas liberated when the experimentwas repeated by using 5.0 g of small marble chips.

Time/min

0 ½ 1 1 ½ 2 2 ½ 3 3 ½ 4

Volume ofcarbondioxide /cm3

0.00 20.00 29.00 35.00 38.00 40.00 41.50 41.50 41.50

TABLE 1


9

8

7


9

8

7

SULIT 4541/3


6

Based on the data in (b) and Table 1, draw the graphs of volume of carbondioxide gas liberated against time for both the experiments by using the sameaxes.

[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 tomeat that is cut into big pieces. Explain why.

………………………………………………………………………………

………………………………………………………………………………

………………………………………………………………………………

[3 marks]

SULIT 4541/3


7

SULIT 4541/3


8

(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 theresponding variable

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

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

(iii) Fixed variable.............................................................

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

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

(iii) The way to maintain the fixedVariable

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

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

[3 marks]

SULIT 4541/39

Meta

Metal L Metal M

Salt solution L1.0 mol dm-3

FIGURE 2

2. An experiment was carried out to construct an electrochemical series of metals. Figure 2shows the voltaic cell set up to measure the potential difference between metal L and M.

The experiment was repeated by replacing metal M with metal J and Q .

Dc

V

4541/3

A

CDIAGRAM 2

iagram 2.1 shows the potential difference of thrells using the pairs of metal L and M, L and J and

B

[Lihat sebelahSULIT

.1

ee voltmeters A, B and C for the voltaicL and Q respectively.

SULIT 4541/3


10

Pair of Metals VoltmeterPotential

difference(V)Positiveterminal

L and M A L

L and J B L

L and Q C Q

TABLE 1

(a) Record the voltmeter readings for the pairs of metals in Table 1.

(b) State the hypothesis of the experiment

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

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

(c) Arrange J, L, M and Q metals in the descending order in the electrochemical series

………………………………………………………………………………….

(d) Iron metal is located between metal M and metal L in the electrochemical series.State which metals are more electropositive and which are less electropositive than iron.

More electropositive than iron:...........................................................................

Less electropositive than iron :...........................................................................

(e) By using the data in Table 1, suggest the possible voltage, if M and Q metals areused as electrodes in a voltaic cell.

………………………………………………………………………………….

SULIT 4541/3


11

3

You are given some iron nails, magnesium ribbon and copper strip .Wit reference to the above statement, plan a laboratory experiment to investigate theeffect of other metals on the rusting of iron.

Your planning should include the following aspects:

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

[17 marks]

END OF QUESTION PAPER

A more electropositive metal acts as a sacrificial metal whichitself corrodes to protect iron from rusting

SULIT 4541

4541Marking SchemeChemistry Peper 1October

1 1/4 jam



MARKING SCHEME

CHEMISTRY

Paper 1

UNTUK KEGUNAAN PEMERIKSA SAHAJA

Skema Pemarkahan ini mengandungi 2 halaman bercetak.

SKEMA PERMARKAHANCHEMISTRY 1

NoSoalan Jawapan

No.Soalan Jawapan

No.Soalan Jawapan

No.Soalan Jawapan

1 C 14 A 27 B 40 D

2 D 15 A 28 D 41 A

3 C 16 D 29 C 42 B

4 A 17 D 30 D 43 A

5 B 18 B 31 C 44 D

6 C 19 D 32 B 45 B

7 A 20 C 33 A 46 D

8 C 21 D 34 D 47 D

9 B 22 B 35 C 48 B

10 B 23 C 36 B 49 C

11 C 24 A 37 C 50 C

12 B 25 B 38 D

13 C 26 A 39 C

1

4541/1Chemistry 2Skema PemarkahanOctober 20091 1/4 hours



CHEMISTRY

Paper 2

MARKING SCHEME


This marking scheme consists of 9 printed pages.

2

SECTION A

No. Rubric Mark

1 (a)

(b)

(c)

(d)

(e)

P: liquidS: solid

1. Particles of Q held together by weak intermolecular forces2. A small amount of heat energy is required to overcome

Diagram1. label2. functional apparatus

1. label of axis2. shape of graph

11

1

11

11

11…9

Time ( min)

Temperature / oC

3

2 (a) Sodium and magnesium // sodium and aluminium //magnesium and aluminium 1

(b) Halogen 1

(c) 2.8.3 1

(d) (i) Sodium, magnesium, aluminium, chlorine, argon 1

(ii) The proton number // the positive charge increasesfrom sodium to argon

The attraction by the nucleus on the electronsin the first three occupied shells become stronger

1

1…2

(e) (i) Sodium burnt rapidly and brightly with a yellow flame //White fumes liberated // white solid formed 1

(ii) 2Na + Cl2 → 2NaCl[Formula of reactants and product are correct][Balanced equation]

11… 2

(iii) has high melting / boiling point // conduct electricityin the molten state or aqueous solution // soluble in water 1

10

3 (a)

(b) (i)(ii)

(iii)(iv)

(c) (i)(ii)

(iii)(iv)

(d)

H+ , Cu2+ , SO42- , OH-

Copper electode becomes thicker//brown solid is depositedCu2+ + 2e CuElectrical energy to chemical energyOxygen

(from zinc plate to copper plate)Oxidation0 to +2Increases

Zn + Cu2+ Cu + Zn2+

1

1111

1111

1...10

4

4 (a) (i) Iron and carbon1

(ii)

[ Suitable diagram ] 1[ Label iron & carbon atom] 1……….. 2

(iii) heavy 1

(b) (i) Chloroethene // Vinylchloride 1

(ii) Not easily biodegradable 1Cause blockage of drainage systems / flash floods 1

ORGive out harmfull / poisonous / toxic gases 1Cause air pollution 1 ………….2

(iii)

Type of glass Uses

…Fused glass…

…Soda-lime glass…

…Lead crystal glass...

3

10

Iron atom

Carbon

5 (a) 1. J : Alkene2. K : Alcohol

11

(b)

(c) (i)

(ii)

B

C

(d)

(e) (i)

(ii)

Ob

C

6 (a)(i)

(ii)

(b)

(c)

(d)(i)(ii)

(e)(i)(ii)

(iii)

(iv)

1utanol

5H11OH

1

1

5

1 + 1

range solution turn to green // Smell of vinegar // The product changelue litmus paper to red

H3CH2CH2CH2OH + 2[O] → CH3CH2CH2COOH + H2O

1

1+1

10

Blue solution turns colourless//intensity of blue colour reduce // Brownsolid substance form // brown solid form // brown deposite 1Green solution turns yellow/brown

Mg + Cu2+ → Mg2+ + Cu 2

Substance/particles loss/donate an electrons 1

0 to +2 1Copper(II) sulphate // Copper(II) ion 1

Redoxs 10 // zero 1

Oxidizing agent // oxisidise ferum(II) sulphate/ferum(II) ion 1

Chlorine water// asidified potassium manganate(VII) solution // asidifiedpotassium dichromate(VI) solution

1

10

6

SECTION B

7 (a) Empirical formula1. Formula that shows the simplest ratio2. of atom of each element in compoundMolecular formula1. Formula that shows actual number2. of atom of each element in compound

2

1 .............3(b) (i)

Element C H

Number ofmoles (mol) 12

7.85= 7.14

1

3.14= 14.30

Ratio of moles14.7

14.7= 1

14.7

30.14≈ 2

Empirical formula for alkene X is CH2

1

1

1

(ii) n [ 12 + 2(1)] = 56

14 n = 56n = 4

Molecular formula for the alkene X is :

4 (CH2) C4H8

11

1

(iii) Butene 1

(iv) CnH2n1………..8

(c) 1. Alkane undergoes an addition reaction2. Bromine is added to a double bond3. Unsaturated compound changes to saturated compound //

Double bond changes to single bond4. No more bromine molecules // colourless product is

formed // dibromobutane is formed.5. C4H8 + Br2 → C4H8Br2

11

1

11………5

(d) (i) Hydrogenation 1

(ii) Optimum condition :Temperature : 180 oCCatalyst : Platinum // Nickel

11

(iii) C4H8 + H2 → C4H10 1………4

20

7

8 (a) (i) 1. Both axis are labelled and with unity axis ; volume/cm3 and x axis ; time/s

2. Uniform scale (size of graph must be bigger)3. All points are transfered correctly4. Best fit curve

1

111

(ii) 1. Average rate of reaction = 19.0/1202. = 0.0528 cm3s-1

3. Construct tangen at 210 s4. 0.052 cm3s-1 0.050 ≤ k ≤ 0.054

1111

(iii)

(iv)

1. Boiling point of oil is higher than boiling point of water2. At higher temperature potatoes is faster to cook

1. The higher the temperature, rate of reaction increase2. High temperature, kinetic energy of particles increase//particles

moves faster3. Collision frequency between particles increase4. Effective collision frequency increase

11

1

111

(b)

Type of food additive Example1. X = Preservatives 4. Salt/Sugar/Vinegar/Sodium

nitrite/Sodium nitrate/Benzoicacid/Sodium benzoate

2. Y = Antioxidants 5. Ascorbic acid/Sodium citrate/3. Z = Flavourings 6. Monosodium glutamate/

aspartame/sugar/salt/vinegar/[ester]

1+1

1+1

1+1

20

8

SECTION C

9 (a) 1. Oxidation - increase in oxidation number2. Reduction – decrease in oxidation number

11…2

(b)(i) 1. Fe+2 Fe+3 + e2. Br2 + 2e 2Br –

3. Iron(II) ions lose electrons to become iron(III) ions. Iron(II) ionsare 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 + 2e3. Iron(III) ions gain electrons to become iron(II) ions. Iron(III)

ions are reduced4. Zinc atoms lose electrons to form zinc ions. Zinc atoms are

oxidised(a: any suitable reducing agent)

111

1

111

1…8

(c) Diagram:1. label2. functional apparatus

Procedure:1. Pour dilute sulphuric acid into a U-tube2. Using a dropper, add iron(II) sulphate solution at one side3. and acidified potassium manganate(VII) solution at another side4. Place carbon electrode in each side of the U-tube5. Connect the electrodes to a galvanometer by using connecting

wires//Complete the external circuit6. Record any change that can be observed after a few minutes

Observations:The green colour of iron(II) solution turns to brownThe purple colour of acidified potassium manganate(VII) solution isdecolourised/change to colourless

(a: any suitable cell)

11

11111

1

11…10

20

9

10 (a) (i) Number of mole BaCl2 = 0.025 molFrom the equation,

1 mol of BaCl2 produces 1 mol BaSO4 //0.025 mol of BaCl2 produces 0.025 mol BaSO4

Mass = 0.025 x 233= 5.825 g

1

1

1………3

(ii) [ Suggested answer ]

1. Measure 50 cm3 of barium chloride 0.5 mol dm -3 in a measuringcylinder.

2. Pour the solution into the beaker.3. Measure 50 cm3 of sodium suphate 0.5 mol dm -3 in a measuring

cylinder.4. Pour the solution into the beaker containing barium chloride

solution.5. Stir the mixture with glass rod and rinse with distilled water.6. Filter the precipitate.7. Dry the salt using 2 pieces of filter paper.

1

11

1

111…… ...7

(b) [Procedure]1. Measure 50 cm3 of barium chloride 0.5 mol dm -3 in a measuring

cylinder.2. Pour the solution into the plastic cup/beaker.3. Record the initial temperature1. Measure 50 cm3 of sodium sulphate 0.5 mol dm -3 in a measuring

cylinder.2. Pour the solution into the plastic cup/beaker.3. Record the initial temperature4. Add the barium chloride solution into the sodium sulphate5. Stir the mixture with thermometer6. Record the highest/maximum temperature

7. [Data]

Initial temperature of BaCl2 solution = T1 oCInitial temperature of Na2SO4 solution = T2 oCHighest temperature = T3 oC

[Calculation]8. Average initial temperature = (T1 + T2)/2 = T4

oC9. Temperature change = T3 – T4

10. Heat change = (50+50) x 4.2 x (T3 – T4) J = Q J11. No. of mole BaSO4 = No of mole BaCl2 = No of mole Na2SO4

= (0.5 x 50)/1000 = n mol12. Heat of Precipitation of BaSO4

ΔH = - Q / 1000n kJ mol-1 Max 10

20

1

4541/1Chemistry 3Skema PemarkahanOctober 20091 1/4 hours



CHEMISTRY

Paper 3

MARKING SCHEME


This marking scheme consists of 9 printed pages.

2

PAPER 3

1 ( a )

Score Rubric3 [ Able to state all the 11 volume or burette readings correctly ]

2 decimal places Unit cm3

Suggested answer0.00, 9.50, 18.10, 25.50, 30.10, 34.50, 38.10, 40.00, 41.50, 41.50, 41.50 or

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 ]0 No response or wrong response

1 (b)

Sco

re

Rubric

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

1. Time /minute2. 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

Buretreading/cm3

49.60 40.10 31.50 24.10 19.50 15.10 11.50 9.60 8.10 8.10 8.10

Volumeof 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 ofgas liberated] // [Able to design table without unit]

1[Able to give idea on table ]Suggest answer: 2 rows x 11 columns

3

1 (c)

Score Rubric3 [ 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 againsttime 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 againsttime with at least 4 items abovebelow correctly]

1 [ Able to manipulate two items correctly ]0 No response or wrong response

1 ( d )

Score Rubric3 [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 largepieces of marble chips of the same mass, course the time taken for reactionmore 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 forreaction 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 forreaction more faster when size of reactant smaller // rate of reaction depend onthe size of reactant


4

1 (e)

Score Rubric3 [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

increases2 [Able to give incomplete relationship ]

Suggested answer[state the any two items above]

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


1 (f)

Score Rubric3 [ 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 chipsResponding variable :Rate of reaction // time Measure the volume of gas collected

at half-minute intervalFixed variable :Mass of marble, volume ofhydrochloric acid, temperature

Use the same mass/5.0 g marble,same volume/50 cm3 andconcentration/ 0.1 mol dm-3

hydrochloric acid, same tepperaturein 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 variablescorrectly // any two action correctly]


5

QuestionNumber

Rubric Score

2(a)

[Able to write potential difference with two decimal correctly]Example

Pair of metals Potentialdifference(V)

Positive terminal

L and M 1.00 LL and J 1.60 LL and Q 0.40 Q

3

[Able to write potential difference almost correct]Example


Positive terminal

L and M 1.0 LL and J 1.6 LL and Q 0.4 Q

2

[Able to write potential difference incomplete or in range]Example


Positive terminal

L and M 1.0 - 1.5 LL and J 1.5 - 2.0 LL and Q 0 - 0.5 Q

1

[ No response or wrong response] 0

QuestionNumber

Rubric Score

2(b)

[Able to give the hypothesis accurately]Example:The further the distance between two metals in the electrochemicalseries, the higher the potential difference / voltage

3

[Able to give the hypothesis almost accurately]Example:The further the distance between two metals, the higher potentialdifference/voltage // vice versa

2

[Able to state an idea of hypothesis]Example:The distance between two metals the higher affects the potentialdifference

1


6

QuestionNumber

Rubric Score

2(c)

[Able to arrange the metals in the electrochemical series indescending order correctly]Answer: :J, M, L, Q

3

[Able to arrange the metals almost correctly]Example:J,M, Q

2

[Able to state an idea to arrange the metals]Example:J metal is higher position compared to the other metals(M/L/Q)

1


QuestionNumber

Rubric Score

2(d)

[Able to classify the metals correctly]Answer: :More electropositive : J, MLess electropositive : L, Q

3

[Able to classify the metals almost correctly]Example:More electropositive : J, MLess electropositive : L/QorMore electropositive : J/ MLess electropositive : L, Q

2

[Able to state an idea to arrange the metals]Example:1. More electropositive : L/ Q

Less electropositive : J/ M

2. More electropositive : L, QLess electropositive : J, M

1


QuestionNumber

Rubric Score

2(e)

[Able to predict correctly]Answer: 1.40V 3

[Able to predict almost correctly]Example:

1.402

[Able to state an idea to arrange the metals]Example:Reading is higher than 1.0 / lower than 1.6

1


7

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]

3 (b) - variables

Score Rubric

3

[ Able to state All variables correctly ]

Suggested answer :Manipulated variable : Different types of metals// Different metalsResponding variable : Rate of rusting // Rusting of ironConstant 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]

8

3 (c) - hypothesis

Score Rubric3 [Able to give the hypothesis accurately]

Suggested answer :When a more electropositive metal is in contact with iron, the metal inhabitsrusting // When a less electropositive metal is in contact with iron, the metalspeed up rusting // Iron rusts faster when in contact with metal lesselectropositive

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 inhabitsrusting


3 (d) - Apparatus and materials

Score Rubric

3

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

Suggested answer :Apparatus : Three test tubes, test tube rackMaterials : sand paper, three iron nails, magnesium strip, copper strip, hotagar/jelly solution mixed with potassium hexacyanoferrate(III) solution andphenolphthalein indicator

2

[ Able to give the list of the apparatus and substances correctly and but notcompletely]

Example :List of apparatus and materialsTest tube, iron nail, magnesium, copper,water, potassiumhexacyanoferrate(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]

9

3 (e) - Procedure of the experiment

Score Rubric

3

[ Able to state all procedures correctly ]

Suggested answer :1. Clean all the metal strips with sand paper2. Coil the metal strip around the iron nails and then put in the each test tube3. Pour the same volume of hot agar-agar/jelly solution has been mixed with

potassium hexacyanoferrate(III) and phenolphthalein indicator4. Leave the test tubes aside for one day5. Compare the intensity of the blue and pink colour in each test tube and

recorded

2[ Able to state 3 steps of procedures correctly ]Example : Steps 2,3,5

1[ Able to state 2 steps of procedures correctly ]Steps 2,3


3 (f) - Tabulation of data

Score Rubric

3

[ Able to exhibit the tabulation of data correctly ]

Tabulation of data has 3 columns and 3 rowsExample :

Test tube A B CIntensity ofblue colourIntensity ofpink colour

2

[ Able to exhibit the tabulation of data less accurately ]

Tabulation of data has 6 columns and 2 rowsExample :

Test tube A B CObservation

1[ Able to state an idea about the tabulation of data ]Tabulation of data has 2 columns and 1 rows or 1 colums and 1 rows


Total 3 × 6 = 18Max 17

kimia 123 dan skema

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