[uks] Chemistry 2004(mock) Paper2(e)

There are 50 questions in this paper. Choose the best answer for each question. 1.

2.

Which of the following is most likely to be a pure compound? A.

a white powder which dissolves in water

B.

green crystals which melt at 58 oC

C.

a colourless liquid which boils over the range 55 to 60 oC

D.

a liquid which gives two fractions when distilled

Which of the following substances is an element and forms crystals containing small molecules?

3.

A.

copper

B.

diamond

C.

ice

D.

iodine

Which statement could be made about a new element, symbol Ha, which has seven electrons in the outermost shell of its atoms? A.

It is monatomic.

B.

It forms a covalent compound with hydrogen.

C.

It forms a positive ion Ha+.

D.

It forms covalent compounds with Group I elements.

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4.

5.

6.

7.

An element X has atomic number 3. Which statement about X is correct? A.

It forms ions by gaining electrons.

B.

It is a gas at room temperature and pressure.

C.

It is Group III of the Periodic Table.

D.

It reacts with cold water.

Solid lead(II) bromide is a non-conductor of electricity because A.

it is a covalent compound.

B.

it is not soluble in water.

C.

the lead and bromide ions are not freely moving.

D.

lead conducts electricity but bromine does not.

Which of the following objects is LEAST likely to contain titanium? A.

missile

B.

water tap

C.

bicycle frame

D.

artificial joint

Tin plating can be used to prevent iron cans from rusting because A.

tin is higher than iron in the electrochemical series.

B.

the tin protects the iron from exposure to air.

C.

tin corrodes more readily than iron.

D.

the tin and the iron readily form an alloy which does not corrode.

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8.

Which diagram represents the structure of an alloy? A.

B.

C.

D.

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9.

Which of the following pairs of metals would be expected to give the largest voltage when they are used as electrodes in a simple chemical cell using potassium nitrate solution as the electrolyte? A.

Zn and Pb

B.

Mg and Ag

C.

Pb and Mg

D.

Fe and Mg

10.

A zinc-carbon cell is connected to a voltmeter as shown in the above diagram.

Which of the following statements concerning the set-up is

INCORRECT? A. c

Electrons flow from the zinc case to the carbon rod in the external circuit.

B.

The zinc case gradually becomes thinner as the cell discharges.

C.

Manganese(IV) oxide acts as an oxidizing agent.

D.

Ammonium chloride acts as a reducing agent.

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11.

In which of the following compounds is the oxidation number of sulphur +2? A.

NaHSO 3

B.

Na2SO3

C.

Na2SO4

D.

Na2S2O3

12. Which of the following is NOT an example of oxidation? A.

Converting iron(III) salts into iron(II) salts

B.

Converting magnesium atoms into magnesium ions

C.

Dissolving of a copper anode during electrolysis

D.

Liberating chlorine from a chloride

13. The action of dilute nitric acid on zinc is represented by the following equation: x HNO3(aq) + y Zn(s) → y Zn(NO3)2(aq) + z H2O(l) + 2NO(g) The values of x, y and z in the balanced equation are A.

3, 4 and 1.

B.

3, 8 and 2.

C.

4, 3 and 2.

D.

8, 3 and 4.

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14. A student tries to plate a copper ring with nickel using the set-up below: d.c. power supply

electrolyte nickel rod

copper ring

Which of the following combinations is correct? Anode

Cathode

Electrolyte

A.

copper ring

Nickel rod

Ni2+(aq)

B.

nickel rod

copper ring

Ni2+(aq)

C.

copper ring

Nickel rod

Cu2+(aq)

D.

nickel rod

copper ring

Cu2+(aq)

15. Which of the following statements about a solution of hydrogen chloride in water is correct? A.

The hydrogen chloride exists as molecules in the solution.

B.

The hydrogen chloride is slightly ionized in water.

C.

The pH value of the solution is greater than 7.

D.

The solution conducts electricity.

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16. The apparatus was set up as shown below.

aqueous sodium hydroxide

solid Z heat

moist universal indicator paper

When the test tube was heated, the indicator paper turned blue. What could be solid Z? A.

aluminium oxide

B.

ammonium sulphate

C.

calcium hydroxide

D.

copper(II) sulphate

17. Which of the following solutions would have the lowest pH value? A.

0.1 M H2SO4

B.

0.1 M HCl

C.

0.1 CH3COOH

D.

0.1 M NaOH

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18. The mass of solid sodium hydrogencarbonate required for completely neutralizing 25.0 cm 3 0.1 M of a tribasic acid solution is (Relative atomic masses: H = 1.0, C = 12.0, O = 16.0, Na = 23.0) A.

0.21 g

B.

0.42 g

C.

0.63 g

D.

0.84 g

19. When 250 cm 3 of 2.00 M hydrochloric acid are added to 13.0 g of zinc, the volume of gas produced at room temperature and pressure is (Relative atomic mass: Zn = 65.0, molar volume of gas at room temperature and pressure = 24 dm3) A.

2.40 dm 3

B.

4.80 dm 3

C.

6.00 dm3

D.

12.0 dm 3

20. The oxide of a metal M contains 31.6 % by mass of oxygen. If the relative atomic mass of metal M is 52, what is the simplest formula for the oxide of M? (Relative atomic mass: O = 16.0) A.

M2O

B.

MO

C.

MO2

D.

M2O3

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21. If 1 g of oxygen gas contains X molecules, how many molecules are present in 1 g of helium gas? (Relative atomic masses: He = 4.0, O = 16.0) A.

X

B.

4X

C.

8X

D.

16X

22. Which of the following expressions represents the mass of a chlorine molecule? (Relative atomic mass: Cl = 35.5; Avogadro constant = 6.02 × 1023 mol-1)

A. B. C. D.

1 35.5 × 6.02 × 10 23 35. 5 2 × 6. 02 × 10 23 35.5 6. 02 × 10 23 2 × 35. 5 6. 02 × 10 23

g

g

g g

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23. What volume of water, when added to 25 cm3 of 2 M hydrochloric acid, would give a 0.2 M solution of the acid? A.

10 cm3

B.

100 cm3

C.

225 cm3

D.

250 cm3

24. Which statement is correct for all exothermic reactions? A.

A catalyst is needed for the reaction to take place.

B.

Heat is absorbed during the reaction.

C.

The products of the reaction have less energy content than the

reactants. reactants. D.

They are reactions which require heat to start.

25. Which of the following would NOT reduce the amount of pollutants in the atmosphere? A.

reducing the lead content of petrol

B.

using fuels of low sulphur content

C.

building tall chimney for factories

D.

installing electrostatic precipitators in incinerator chimneys

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26. A glass of sweet wine is left on a dining table. After two days, the wine becomes sour. Which of the following type of reactions accounts for this change? A.

oxidation

B.

condensation

C.

fermentation

D.

esterification

27. Which diagram represents a polymer formed by addition polymerization? A.

B.

C.

D.

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28. Which of the following statements concerning the compound, CH3COOCH2CH3, is correct? A.

It is a food preservatives.

B.

It has a pleasant smell.

C.

Its systematic name is methyl ethanoate.

D.

It is an electrolyte.

29. Which of the following statements concerning soapless detergents is correct? A.

They are all biodegradable.

B.

They form scum with sea water.

C.

The molecule of soapless detergent has a hydrophilic head and a

hy

hydrophobic tail. D.

sodi

They can be made from the reaction between vegetable oils and sodium hydroxide.

30. The nitrogen present in some fertilizers helps plants A.

to produce fats.

B.

to produce sugars.

C.

to produce proteins.

D.

to undergo photosynthesis.

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31. Which of the following combinations is correct?

A. B. C. D.

Chlorine bleach The active ingredient is Cl-(aq). Its bleaching effect is not permanent. Its bleaching action faster. It is used to bleach silk.

is

Sulphur dioxide bleach The active ingredient is SO32-(aq). Its bleaching effect can be last for a longer period of time. Its bleaching action is slower. It is used to bleach paper.

32. A method of collecting a gas is shown below.

Which of the following gases is most suitably collected by this method? A.

ammonia

B.

chlorine

C.

oxygen

D.

carbon dioxide

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33. Which of the following combinations would cause “striking back” in Bunsen flame? Air hole

Gas supply

A.

fully closed

too weak

B.

fully closed

too strong

C.

fully opened

too weak

D.

fully opened

too strong

34. A mixture of three gases was passed through the apparatus shown in the diagram. Only one gas was collected in the gas jar. mixture of gases

gas jar

dilute sulphuric acid

aqueous sodium hydroxide

water

Which of the following could the mixture have been? A.

ammonia, carbon dioxide and hydrogen

B.

carbon dioxide, sulphur dioxide and hydrogen chloride

C.

carbon dioxide, hydrogen and oxygen

D.

hydrogen, nitrogen and sulphur dioxide

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35. The diagram shows a chromatogram of several inks.

black

blue

brown

green

red

yellow

Which statement is correct? A.

Black ink can be made by mixing green, red and yellow inks.

B.

Brown ink can be made by mixing blue and red inks.

C.

Yellow ink can be used to make brown ink.

D.

Yellow ink may be present in green ink.

36. Which of the following metals is/are present in solder? (1)

copper

(2)

lead

(3)

iron A.

(1) only

B.

(2) only

C.

(1) and (2) only

D.

(2) and (3) only

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37. When crude oil is fractionally distilled in the laboratory, the first fraction obtained, compared to later fractions, (1)

have lower boiling points.

(2)

have lower flammability.

(3)

are more viscous. A.

(1) only

B.

(2) only

C.

(1) and (3) only

D.

(2) and (3) only

38. Which of the following is/are common characteristic(s) of thermoplastics? (1)

They all burn before melting.

(2)

They can be moulded more than once.

(3)

They are all made from compounds containing C=C bond. A.

(1) only

B.

(2) only

C.

(1) and (2) only

D.

(2) and (3) only

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39. In the manufacture of sulphuric acid by the Contact Process, which of the following steps require the use of a catalyst? (1)

the burning of sulphur to form sulphur dioxide

(2)

the oxidation of sulphur dioxide to sulphur trioxide

(3)

the conversion of sulphur trioxide to sulphuric acid. A.

(1) only

B.

(2) only

C.

(1) and (2) only

D.

(2) and (3) only

40. Which of the following metals can be obtained by reducing their oxides with carbon? (1)

iron

(2)

calcium

(3)

lead A.

(1) and (2) only

B.

(1) and (3) only

C.

(2) and (3) only

D.

(1), (2) and (3)

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41. The electronic structure of a compound formed between elements X and Y is shown below.

Y

X

Y

Y Which of the followings about the compound are correct? (1)

An atom of X has five electrons in the outermost shell.

(2)

Element Y exists as a diatomic molecule under ordinary conditions.

(3)

Element X has an oxidation number of +3 when it forms a compound with sodium. A.

(1) and (2) only

B.

(1) and (3) only

C.

(2) and (3) only

D.

(1), (2) and (3)

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42. Which of the following pollutants are found in the exhaust from cars using petrol as fuel? (1)

CO

(2)

SO2

(3)

NO2 A.

(1) and (2) only

B.

(1) and (3) only

C.

(2) and (3) only

D.

(1), (2) and (3)

43. Which of the following statements concerning sulphur dioxide are correct? (1)

It can be prepared by heating copper turnings with concentrated sulphuric acid.

(2)

It is denser than air.

(3)

It can be absorbed by sodium hydroxide solution. A.

(1) and (2) only

B.

(1) and (3) only

C.

(2) and (3) only

D.

(1), (2) and (3)

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44. The following three different solutions were electrolysed using inert electrodes. Which of the solutions produced hydrogen at the cathode? (1)

aqueous sodium chloride

(2)

concentrated hydrochloric acid

(3)

dilute sulphuric 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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Directions:

Each question below (Question Nos. 45 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 opinion 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 2nd statement is NOT a correct explanation of the 1st statement. C. The 1st statement is false but 2nd statement is true. D. Both statements are false. 45.

1st statement Isotopes of a given element have the same mass.

2nd statement All isotopes of a given element have the same mass number.

46.

Potassium is an oxidizing agent.

Each potassium atom loses an electron when it reacts.

47.

Concentrated sulphuric acid can char a piece of cloth.

Concentrated sulphuric acid is highly corrosive.

48.

Cracking in the petroleum industry is a physical change.

It involves the breaking up of large hydrocarbon molecules into smaller one.

49.

The yellow colour of bromine water disappears when it is mixed with sodium sulphite solution.

The bromine water is reduced to bromide ions by the sulphite ions.

50.

Vinegar can be used as a preservative for cucumbers.

The acid in vinegar kills the bacteria and prevents the food from going bad.

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