hkcee chem samuel 2 e

8/10/2019 Hkcee Chem Samuel 2 e

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CE Chemistry

Paper II

Dr. Samuel Chong

Dr. Samuel Chong

AB C 04 05 (SWA)

05 06


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2007-CE-CHEM 2-1

2007CE

CHEM2

CE Mock 2007

CHEMISTRY PAPER 2

11.00 am 12.00 noon (1 hour)

1.

Read carefully the instructions on the Answer Sheet and insert the information

required (including the Subject Code) in the space provided.

2. When told to open this book, you should check that all the question are there. Look

for the words END OF PAPER after the last question.

3. ALL question carry equal marks.

4. ANSWER ALL QUESTIONS. You should mark all your answer on the Answer

Sheet.

5.

You should mark only ONEanswer for each question. If you mark more than oneanswer, you will receive NO MARKSfor that question.

6. No marks will be deducted for wrong answers.


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2007-CE-CHEM 2-1 -1- Go on to the next page

By Dr. Samuel Chong Chemistry Team

There are 30 questions in Section A and 20 questions in Section B.

Atomic numbers and relative atomic masses of elements can be obtained from the

Periodic Table.

Section A

1. Which of the following statements concerning the elements in the same group of

the periodic table are correct?

(1) The atomic size increases down the group.

(2) The reactivity of elements increase down the group.

(3) The number of electron shells increases.

A (1) and (2) onlyB (1) and (3) only

C (2) and (3) only

D (1), (2) and (3)

2. Consider the following information:

Substance Melting point/ Electrical conductivity at

room temperature

Solubility in water

W -31 poor slightly soluble

X 49 poor insoluble

Y 240 good insoluble

Z 750 poor very soluble

Which substance has a simple molecular structure and is a solid at roomtemperature ?

A. WB. XC. Y

D. Z


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3. Element X consists of two isotopes,10

X and11

X. If the relative atomic mass of Xis 10.8, what is the relative abundance of the

10X isotope?

A. 20%

B. 40%

C. 60%

D. 80%

4. Which of the following statements concerning flame test are correct?

(1) Elements in the same group give rise to similar flame colour.(2) A platinum wire should be used to dip the sample.

(3) The sample should be put in the non-luminous frame.

A. (1) and (2) onlyB. (1) and (3) only

C. (2) and (3) onlyD. (1),(2) and (3)

5. The melting point and boiling point of substance X are 361and 780

respectively. X conducts electricity without decomposition in its molten state. X

probably has

A. A giant covalent structure.

B. A giant metallic structure.

C. A simple molecular structure.D. A giant ionic structure.

6. The following equation represents the reaction of chlorine with dilute sodium

hydroxide solution at room temperature :

Cl2(g) + 2NaOH(aq) NaCl(aq) + NaOCl(aq) + H2O()

Which of the following statements concerning this reaction is/are correct?

(1) Sodium hydroxide acts as an oxidizing agent.

(2) The oxidation number of chlorine changes from 0 to -1.

(3) The oxidation number of chlorine changes from 0 to +1.

A. (1) only

B. (2) only

C. (1) and (3) onlyD. (2) and (3) only


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7. Paper chromatography can be used to separate

A. sand from water.

B. different components in ink.C. oxygen and nitrogen from air

D. copper(II) sulphate from water.

8. Iron cans used for canning food are found that tin is coated on its surface instead

of using zinc. Which of the following statement is correct?

A. the reactivity of tin is higher than zinc.B. zinc ions are toxic but tin ions are non-toxic

C. tin is more resistant to corrosion than zincD. tin prevents iron cans from rusting by sacrificial protection.

9. Which of the following phenomenon does NOT involve a chemical change?

A. Cracking of oil

B. Burning of candle

C. Sublimation of iodine

D. Rusting of iron

10. Which of the following methods can be used to produce limewater?

(1) Dissolve calcium carbonate in excess water

(2) Limestone is heated and the solid formed is dissolved in excess water

(3) Dissolve quicklime in excess water

A. (1) only

B. (3) onlyC. (1) and (2) only

D. (2) and (3) only


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H C

H

C H3

C

Br

O H

H

11. An organic compound has the following structure :

The systematic name of this compound is

A. 1-bromo-2-methylethanol

B. 1-bromopropan-1-olC. 1-bromopropan-2-ol

D. propan-1-ol

12. Which of the following substances can react with but-1-ene ?

(1) bromine solution(2) ethanol

(3) acidified potassium permanganate solution

A. (1) only

B. (2) only


13. An organic compound X reacts with sodium hydroxide to give a compound with

formula C3H5O2Na. What is compound X?

A. ethanol

B. propane

C. propanoic acid

D. propanol


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H C C C C

H H

H

H

H

H

H

HC HH

H

H C C C C H

H

H

H

H

C

H

H

H

H

H H

X Y

14. Which of the following is / are NOT necessary for the preparation of a standard

solution of a soluble salt?

(1) Pipette

(2) Measuring cylinder(3) Volumetric flask

A. (1)only

B. (2)onlyC. (1) and (3) only

D. (2) and (3) only

15. Compounds X and Y have the following structures :

Which of the following statements about compound X and Y are correct?

(1) They have the same molecular formula but different structural formulae.

(2) They belong to the same homologous series.

(3) They are isomers.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

16. Which of the following equations represents a redox reaction?

A. Mg(HCO3)2+ 2HClMgCl2+ 2CO2+ 2H2OB. PCl3+ Cl2PCl5

C. Fe2+

+ 2OHFe(OH)2

D. NH4+(aq) + OH

(aq)NH3(g) + H2O(l)


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17. Consider the following chemical equation :

2HNO3(aq) + MgCO3(x) Mg(NO3)2(y) + H2O(z) + CO2(g)

Which of the following combinations is correct ?

x y z

A. aq aq lB. aq s aqC. s aq lD. s s l

18. A white solid dissolves in water to give a colourless solution. In the reactionbetween the solution and dilute hydrochloric acid, a colourless gas is evolved. The

solid is probably

A. sodium hydroxide.B. sodium carbonate.

C. magnesium oxide.

D. magnesium carbonate.

19. Which of the following statements concerning members of a homologous series is

INCORRECT?

A. Members of the series contain not only carbon and hydrogen.B. Members of the series can be represented by the same general formula.

C. Members of the series have similar chemical properties.D. Boiling points of members of the series decrease with their relative

molecular masses.

20. Which of the following mixtures would produce the greatest amount of precipitatewhen sodium carbonate solution and calcium chloride solution are mixed?

A. 8 cm3of 2M Na2CO3(aq) + 15 cm3 of 2 M CaCl2(aq)B. 10 cm

3of 2 M Na2CO3(aq) + 10 cm

3of 2 M CaCl2(aq)

C. 15 cm3of 2 M Na2CO3(aq) + 8 cm

3of 2 M CaCl2(aq)

D. 18 cm3of 2 M Na2CO3(aq) + 8 cm

3of 2 M CaCl2(aq)


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21. Which of the following methods can be used to obtain metal ?

(1) heating iron pyrite

(2) heating silver oxide

(3) reducing the lead(II) oxide with carbon

A. (1) and (2) only

B. (1) and (3) onlyC. (2) and (3) only

D. (1), (2) and (3)

22. X, Y and Z are metals. Metal X reacts with dilute hydrochloric acid to liberatehydrogen, but metal Y and metal Z have no reaction with the dilute acid. Y can

displace Z from a solution of the nitrate of Z. Which of the following

arrangements represents the order of increasing reactivity of the three metals?

A. X < Y < Z

B. Y < Z < X

C. X < Z < YD. Z < Y < X

23. The molecular formula of a gaseous element Y is Y2. If the relative atomic massof Y is 16, what is the number of molecules in 128 g of the gas?

(Avogadro's number = 6.02 1023

)

A. 4B. 8C. 4 6.02 1023

D. 8 6.02 1023


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24. There is an unknown compound X which is white solid. When X is warmed withsodium hydroxide solution, a gas is given off which turns moist red litmus paper

blue. A brown solution is formed when chlorine is bubbled into an aqueous

solution of X. X is probably

A. potassium iodide

B. potassium chloride

C. ammonium iodideD. ammonium chloride

25. Copper is heated with concentrated sulphuric acid. Which of the followingcombinations is correct ?

Gas evolved Colour of solution formed

A. hydrogen blueB. hydrogen yellowC. sulphur dioxide blue

D. sulphur dioxide yellow

26. In an experiment, sulphur dioxide is passed into a test-tube containing acidifiedpotassium permanganate solution. The colour of the solution gradually changes

from purple to colourless. Which of the following statements concerning the

experiment is correct?

A. A displacement reaction occurs.

B. The purple colour is due to the presence of Mn2+

(aq) ionsC. Sulphur dioxide is oxidized to sulphate

D. The oxidation number of manganese changes from +7 to +3 in the

reaction


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27. X is an organic compound. The following are the results of several tests on X.

The structural formula of X may be

A. CH3CH=CH2.

B. CH3CH2CH2OH.C. CH3CH2CO2H.

D. CH3CO2CH3.

Test Results

(1) Treating Xwith potassium

carbonate solution

No observation

(2) Treating Xwith a solution of

bromine in 1,1,1-trichloroethane

No observation

(3) Heating Xwith acidified

potassium dichromate solution

No observation


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Directions: Each question below (Question Nos. 28 to 30) consists of two separate

statements. Decide whether each of the two statements is true or false; if both are true,

then decide whether or not the second statement is a correct explanation of the first

statement. Then select one option from A to D according to the following table:

A.

Both statements are true and the 2nd statement is a correct explanation of the 1st

statement.

B. Both statements are true but the 2ndstatement is NOT a correct explanation of the

1st statement.C. The 1st statement is false but the 2nd statement is true.

D. Both statements are false.

1ststatement 2

ndstatement

28.

The active ingredient of sulphur

dioxide bleach is SO42

.

Sulphur dioxide bleaches by

reduction.

29.

The reaction of ethanoic acid withethanol is a neutralization.

Ester is one of the productsformed in esterification

30.

Concentrated sulphuric acid can turn

hydrated copper(II) sulphate crystals

black.

Concentrated sulphuric acid is a

dehydrating agent.

END OF SECTION A


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31. Arrange the pH value of soap, window cleanser and rain water in descending

order.

A. rain water > soap > window cleanserB. window cleanser > rain water > soap

C. window cleanser > soap > rain water

D. soap > window cleanser > rain water

32. A sample of an oxide of metal Y of mass 39.90 g in which 27.90 g is metal Y.What is the mole ratio of Y to oxygen in the oxide?

(Relative atomic masses: O = 16.0, Y = 55.8).

A. 1:1

B. 1:2

C. 2:3D. 3:4

33. The mass of one mole of silicon atoms is twice that of one mole of nitrogen atoms.

Which of the following statements is/are correct ?

(1) The number of atoms in 4 g of silicon and 2 g of are the same.

(2) 4 g of silicon and 2 g of nitrogen each occupy the same volume at roomtemperature and pressure.

(3) The number of atoms contained in one mole of silicon is twice that containedin one mole of nitrogen.

A. (1) only

B. (2) only


34. Which of the following statements concerning a zinc-carbon cell are correct?

(1)The ammonium chloride in the cell acts as an electrolyte.

(2)

Manganese(IV) oxide acts as an reducing agent.(3)The zinc case gradually becomes thinner as the cell discharges.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)


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1 Mp otassiu miodide solution

sal t br idge

c a r b o n e l e c t r o d e X c a r b o n e l e c t r o d e

1 Mir on (III)sulphate solution

V

fl o w of el e ctr ons

35. Consider the set up shown below:

Which of the following statements are correct ?

(1)The solution around electrode X turns brown.(2)The mass of electrode X decreases.

(3)Oxidation occurs at electrode X.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

36. Which of the following changes would occur at the electrodes in the electrolysisof 1 M copper(II) chloride solution using carbon as the cathode and copper as

anode?

Cathode Anode

A. oxygen liberated chlorine liberatedB. copper dissolved hydrogen liberated

C. copper formed copper dissolved

D. copper dissolved copper formed

37. Which of the following statements about a solution of hydrogen chloride in water

is INCORRECT?

A. It exists as ions in the solution

B. It is fully ionized in water.

C. The reaction between the solution and aqueous ammonia isendothermic.

D. The pH value of the solution is less than 7.

Carbon electrode X Carbon electrode Y

Salt brid e

1 M potassium

iodide solution

1 M Iron(III)

sulphate solution

Flow of electrons


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38. In an experiment, excess marble chips are allowed to react with 200cm3of 0.5 M

hydrochloric acid at room temperature and pressure. The volume of gas given outis measured. The experiment is then repeated with the same amount of marble

chips and 100 cm3of 1 M hydrochloric acid. Which of the following graphs best

shows the result?(the dotted curve shows the original result)

A. B.

C. D.

39. 2.2 g of an acid crystals, (COOH)2 2H2O were made up to 250 cm3of solution.

25 cm3of the solution required 29.6 cm

3of 0.12 M sodium hydroxide solution for

complete neutralization. What is the basicity of the acid?

A. 1

B. 2

C. 3D. 4


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40. Which of the following substances can be used to distinguish betweenconcentrated nitric acid and concentrated sulphuric acid ?

(1)

potassium carbonate powder

(2)copper turnings(3)hydrated copper(II) sulphate solution


C. (2) and (3) only

D. (1), (2) and (3)

41. Which of the following process would produce a coloured gas?

A. adding calcium to water

B. adding zinc to dilute hydrochloric acid

C. adding copper to concentrated nitric acidD. passing steam over red hot iron

42. A student carried out an experiment to study the rate of reaction, 100 cm3of 1 M

hydrochloric acid are added to a large piece of magnesium at room temperature.

Which of the following modifications would increase the rate of reaction?

(1) The molarity of hydrochloric acid is 2 M instead of 1 M.

(2) Using magnesium ribbons instead of large piece of magnesium.

(3) Using 100 cm3of 1 M sulphuric acid instead of hydrochloric acid.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)


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43. A student prepared soap by heating fat with sodium hydroxide solution for sometime.

He then added the mixture to a beaker of concentrated sodium chloride solution.

A white solid was formed. Which of the following statements concerning thisexperiment is/are correct?

(1)The reaction between fat and sodium hydroxide is saponification(2)The white solid is a soap.

(3)Concentrated sodium chloride solution is added to enhance the cleansing

power of the soap.

A. (1) onlyB. (2) only

C.

(1) and (2) onlyD. (2) and (3) only

44. Which of the following statements concerning propene is INCORRECT?

A. It can undergo addition reaction with bromine in 1,1,1-trichloroethaneB. It can be manufactured by cracking petroleum fractions.

C. It can undergo condensation polymerization.

D. It can be converted by catalytic hydration to an alkanol with structural

formula CH3CH2CH2OH

45. Which of the following statements concerning thermosetting plastics is/arecorrect?

(1) They can be softens or melt again under heating.

(2) There are cross-linkages between polymer chains

(3) They can be used to make electric sockets.

A. (1) only

B. (2) onlyC. (1) and (3) only

D. (2) and (3) only


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46. Which of the following aqueous solutions will liberate only gaseous products atboth electrodes during electrolysis by using carbon electrodes?

(1)

NaOH (aq)

(2)AgNO3 (aq)(3)KCl (aq)


C. (2) and (3) only

D. (1), (2) and (3)

47. Which of the following statements about sulphur dioxide is/are correct?

(1) It acts as reducing agent during the production of sulphuric acid in thecontact process

(2) It bleaches a red petal by oxidation.

(3) It decolorizes bromine water by reduction


C. (2) and (3) only

D. (1), (2) and (3)


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Directions: Each question below (Question Nos. 48 to 50) consists of two separate

statements. Decide whether each of the two statements is true or false; if both are true,

then decide whether or not the second statement is a correct explanation of the first

statement. Then select one option from A to D according to the following table:

A.

Both statements are true and the 2nd statement is a correct explanation of the

1st statement.

B. Both statements are true but the 2ndstatement is NOT a correct explanation of

the 1st statement.C. The 1st statement is false but the 2nd statement is true.

D. Both statements are false.

1ststatement 2

ndstatement

48.Anodization can increase the

corrosion resistance of aluminium.

During anodization, aluminium

object to be anodized is placed at

anode

49.

Scum is produced when sea water

reacts with soap.

Water consists of magnesium ions

can form an insoluble compound with

soap.

50.Propene is unsaturated Polypropene is saturated.

END OF PAPER

hkcee chem samuel 2 e

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