srjc promo 2009 paper 1

SERANGOON JUNIOR COLLEGE General Certificate of Education Advanced Level Higher 2

CHEMISTRY 9647/01

JC1 Promotional Examination 6th October 2009

Paper 1(MCQ) 1 hour Additional Materials: Data Booklet

Multiple Choice Answer

READ THESE INSTRUCTIONS FIRST

On the separate multiple choice answer sheet given,

Write your name, subject title, class in the spaces provided.

Shade correctly the item index number, starting with the number “1” and the last 4 numbers of

your FIN/NRIC number.

Eg. If your NRIC is S8906660Z, shade 16660 for the item index number.

There are thirty questions in this paper. Answer all questions.

For each question there are four possible answers A, B, C and D.

Choose the one you consider correct and record your choice in soft pencil on the separate

answer sheet.

Each correct answer will score one mark.

A mark will not be deducted for a wrong answer.

You are advised to fill in the OMR Answer Sheet as you go along; no additional time will be

given for the transfer of answers once the examination has ended.

Any rough working should be done in this question paper.

This document consist of 15 printed pages and 1 blank page

2

SRJC 2009 JC1/H2/Promo/2009 [Turn Over

Section A

For each question there are four possible answers, A, B, C and D. Choose the one you

consider to be correct.

1 Which of the following describes the correct dilution procedure to obtain 250 cm3 of

0.004 mol dm-3 hydrochloric acid from a stock solution of concentration of 0.1 mol dm-3?

A Pipette 25.0 cm3 of the stock solution into a 250 cm3 volumetric flask and top up

to the mark with distilled water

B Pipette 20.0 cm3 of the stock solution into a 250 cm3 volumetric flask and top up


C Pipette 10.0 cm3 of the stock solution into a 250 cm3 volumetric flask and top up


D Pipette 5.0 cm3 of the stock solution into a 250 cm3 volumetric flask and top up to

the mark with distilled water

2 1.97 g of an unknown MCO3 completely reacts with 50.00 cm3 of

0.4 mol dm-3 of hydrochloric acid. What is the molar mass of MCO3?

A 98.5 g mol-1

B 197.0 g mol-1

C 394.0 g mol-1

D 788.0 g mol-1

3 Which of the following is a type of redox reaction?

A NaOH + HCl → NaCl + H2O

B CaCO3 → CaO + CO2

C HCl + AgNO3 → AgCl + HNO3

D 3Br2 + 6OH- → 5Br

- + BrO3

- + 3H2O

3


4 Consider the following half equations:

Cr2O72- + 14H+ + 6e- → 2Cr3+ + 7H2O

Fe2+ → Fe3+ + e-

C2O42- → 2CO2 + 2e

What volume of 0.01 mol dm-3 K2Cr2O7 is required to oxidise 15 cm3 of an acidified

solution of 0.01 mol dm-3 FeC2O4?

A 5.0 cm3

B 7.5 cm3

C 16.7 cm3

D 30.0 cm3

5 When a stream of protons was accelerated across an electrical field, the trajectory of the

protons was as follows.

What would be the angle of deflection when a stream of helium plasma ( +242He ) is sent

through the same electrical field?

A 0.5 o

B 1.0 o

C 2.0 o

D 4.0 o

—

+

p

Angle of deflection = 2.0 o

4


6 What is the electronic configuration of element Ni after it has undergone the 3rd ionisation?

A 1s22s22p63s23p63d7

B 1s22s22p63s23p63d8

C 1s22s22p63s23p63d54s2

D 1s22s22p63s23p63d64s1

7 Alliin is the compound responsible for the characteristic smell of garlic.

What are the values of the bond angles a, b and c in the molecule of alliin?

C C

HH

H

CH2 S

O

CH2 C

NH2

H

COOH

a b c

A 180o 120o 90o

B 120o 107o 109o

C 180o 107o 90o

D 120o 109o 107o

8 Which of the following would give the best indication of the relative strengths of the

intermolecular forces of attraction in liquid hydrogen halides?

A Enthalpy change of solution

B Enthalpy change of formation

C Enthalpy change of vaporisation

D Bond dissociation energies

a

b c

5


9 Which molecule will not form a hydrogen bond with another of its own molecule?

A CH3F

B CH3NH2

C CH3OH

D NH3

10 Two colourless substances, D and E, react to give a coloured substance F. The time

taken when various initial concentrations of D and E used are recorded below:

[D]/mol dm-3 [E]/mol dm-3 Time/s

0.05 0.05 44

0.05 0.10 22

0.10 0.05 44

What is the rate equation for this reaction?

A rate = k [E]

B rate = k [D] [E]

C rate = k [E]2

D rate = k [D] [E]2

11 If the rate of decay of a radioactive isotope decreases from 400 counts per minute to 25

counts per minute after 16 hours, what is its half life?

A 1 hour

B 4 hours

C 8 hours

D 16 hours

6


12 A 14.5 mg of an unknown sample of boron hydride, BxHy was found to occupy a volume

of 188 cm3 at a pressure of 3.59 kPa and 25°C. Which of the following is the molecular

formula of the boron hydride?

A B2H6

B B4H10

C B5H9

D B6H10

13 The value of RT

pVis plotted against p for three gases, L, M and N where p is the pressure,

V is the volume and T is the temperature of the gas.

Which of the following could be the possible identities of the gases?

Gas L Gas M Gas N

A SO2 NH3 H2

B H2 NH3 SO2

C NH3 SO2 H2

D NH3 H2 SO2

p

pV

RT

gas M

gas L

1.0

gas N

7


14 The enthalpy change of reaction between magnesium and water can be measured in the

laboratory.

Mg (s) + 2H2O (l) � Mg(OH)2 (s) + H2 (g)

Which information, other than that obtained in this experiment, is needed to calculate a

value for the enthalpy change of formation of Mg(OH)2 (s) ?

A Enthalpy change of atomisation of magnesium

B Enthalpy change of combustion of hydrogen

C First and second ionisation energies of magnesium

D Lattice energy of magnesium hydroxide

15 Consider the following reactions:

Mg (s) + 2HCl (aq) � MgCl2 (aq) + H2 (g) ∆Hθ = −464 kJ mol-1

MgO (s) + 2HCl (aq) � MgCl2 (aq) + H2O (l) ∆Hθ = −148 kJ mol-1

Given that the enthalpy change of formation of water is −285 kJ mol-1, what is the

enthalpy change of formation of magnesium oxide?

A −31 kJ mol-1

B −327 kJ mol-1

C −601 kJ mol-1

D −897 kJ mol-1

8


16 The graphs below show the variation of the percentage of gaseous products present at

equilibrium, with temperature and pressure.

Which one of the following systems is represented by the graphs?

A N2 (g) + 3H2 (g) 2NH3 (g) ∆H = −92 kJ mol-1

B 3O2 (g) + 4NH3 (g) 2N2 (g) + 6H2O (g) ∆H = −1248 kJ mol-1

C 2N2 (g) + O2 (g) 2N2O (g) ∆H = +82 kJ mol-1

D CO2 (g) + C (s) 2CO (g) ∆H = +173 kJ mol-1

17 For which equilibrium does Kc have no units?

A C (s) + H2O (g) CO (g) + H2 (g)

B Cu2+ (aq) + 4NH3 (aq) [Cu(NH3)4]2+ (aq)

C 2NO2 (g) N2O4 (g)

D CH3OH (l) + CH3CO2H (l) CH3CO2CH3 (l) + H2O (l)

Pressure

% products at

equilibrium

450oC

650oC

9


18 Two reversible reactions are represented below.

Reaction I: 2P2 (g) + Q2 (g) 2P2Q (g)

Reaction II: 2P2Q (g) 2P2 (g) + Q2 (g)

Given that the numerical value Kc for Reaction I is 6, what is the numerical value of Kc

for Reaction II under the same conditions?

A 1

6

B 1

3

C −6

D −3

19 Assuming that the acid is monobasic, which one of the following is a conjugate acid-base

pair?

A H3PO4/HPO4 2-

B H2SO4/HSO4-

C H3PO4/PO43-

D H2SO4/SO42-

20 Which of the following statements about a sample of 1 x 10-7 mol dm-3 nitric acid is true?

A The pH of the solution is 1.0 as nitric acid is a strong acid.

B The pH of the solution is 7.0 as nitric acid is a monobasic acid.

C The pH of the solution is 6.7 as the solution is very dilute.

D The pH of the solution is 7.3 as the solution contains OH- ions from the self-

dissociation of water.

10


Section B

For questions 21 - 30, one or more of the numbered statements 1 to 3 may be correct.

Decide whether each of the statements is or is not correct (you may find it useful to put a tick

against the statements that you consider to be correct).

The responses A to D should be selected on the basis of

A B C D

1, 2 and 3

are correct

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct

No other combination of statements is to be used as correct response.

21 The reaction between potassium manganate(VII) in alkaline solution and potassium

methanoate, HCO2K takes place according to the following equation.

2KMnO4 + 3KOH + HCO2K → 2K2MnO4 + K2CO3 + 2H2O

Which statement(s) is/are correct about this reaction?

1 Potassium methanoate acts as a reducing agent.

2 The oxidation number of carbon increased by two units.

3 The oxidation number of manganese increased by one unit.

22 Which of the following statement(s) about ZYX 34

16

32

16

32

15, and is/are correct?

1 Mass of X is smaller than Y.

2 First ionisation energy of X is larger than Z.

3 Y and Z are isotopes.

11



A B C D

1, 2 and 3

are correct

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct


23 Which of the following types of bonds is/are present within NH4Cl?

1 Dative Bonding

2 Covalent Bonding

3 Ionic Bonding

24 The graph below shows how rate of reaction varies with substrate concentration for a

particular enzyme at its optimum temperature. Which of the following can be deduced

from the graph?

1 The reaction is first order at low substrate concentration and zero order at high

substrate concentration.

2 The enzyme is denatured at high substrate concentration.

3 Increasing the temperature by 20oC would lead to a significant increase in the

rate of reaction.

Initial rate of reaction

[Substrate] 0

12



A B C D

1, 2 and 3

are correct

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct


25 A certain reversible reaction R + S T + U, gives the following energy profile

diagram.

Which of the following statement(s) is/are false?

1 The addition of a catalyst lowers Ea but not Ea’.

2 The rate of reaction for the backward reaction is higher than that for the forward

reaction assuming equal concentrations of reactants and products.

3 Increasing temperature will speed up the rate of both forward reaction and

backward reaction.

Ea

Energy/ kJ mol -1

(Reactants)

(Products)

(Transition state)

Reaction pathway

Ea’

13



A B C D

1, 2 and 3

are correct

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct


26 Which of the following statement(s) describe(s) the behavior of noble gases?

1 They behave more ideally down the group when pressure increases.

2 They behave less ideally down the group due to an increase in atomic radius.

3 They behave less ideally down the group due to an increase in relative atomic

mass.

27 Which of the following processes in the Born Haber cycle for magnesium fluoride is/are

endothermic?

1 Mg (g) � Mg 2+ (g) + 2e-

2 F2 (g) � 2F (g)

3 2F (g) + 2e- � 2F- (g)

14



A B C D

1, 2 and 3

are correct

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct


28 The enthalpy level diagram shown represents the dissolving of anhydrous magnesium

chloride in a large volume of water.

Which statement(s) about the process is/are correct? 1 The lattice energy of magnesium chloride is +2526 kJ mol-1.

2 The enthalpy change of hydration of the chloride ion is −384 kJ mol-1.

3 The enthalpy change of solution of anhydrous magnesium chloride is

−132 kJ mol-1.

Energy

Mg2+ (g) + 2Cl- (g)

MgCl2 (s)

MgCl2 (aq)

+2526 kJ mol-1 −1890 kJ mol-1 + 2(−384) kJ mol-1

SRJC 2009


A

1, 2 and 3

are correct

1 and 2 only


29 Compound V decomposes according to the equation:

V (g) W (g) + X

In an experiment, an amount of

results were shown in the diagram below:

What happened in the reaction when the graphs become horizontal?

1 The rate of forward reaction is now equal to the rate of backward reaction

2 The reaction has stopped

3 The concentration of

30 The dissociation of ethylamine, CH

CH3CH

Given that the degree of dissociation of 0.010 mol

which of the following deductions can be made?

1 Concentration of hydroxide ions = 0.010 mol

2 pH of solution = 11.2

3 Value of Kb = 3.48 x 10

Amount (in mol)

15

JC1/H2/Promo/2009

should be selected on the basis of

B C D

1 and 2 only

are correct

2 and 3 only

are correct

1 only

is correct

combination of statements is to be used as correct response.

decomposes according to the equation:

X (g) ∆H = + 173 kJ mol−1

In an experiment, an amount of V was decomposed in a closed container, and the

results were shown in the diagram below:

the reaction when the graphs become horizontal?

The rate of forward reaction is now equal to the rate of backward reaction

The reaction has stopped.

The concentration of V is now equal to concentration of W.

issociation of ethylamine, CH3CH2NH2 is given as follows:

CH2NH2 + H2O CH3CH2NH3+ + OH-

Given that the degree of dissociation of 0.010 mol dm-3 ethylamine is 0.17 at 25

which of the following deductions can be made?

Concentration of hydroxide ions = 0.010 mol dm-3

11.2

= 3.48 x 10-4 mol dm-3

V

W

[Turn Over

D

1 only

is correct

was decomposed in a closed container, and the

The rate of forward reaction is now equal to the rate of backward reaction.

ethylamine is 0.17 at 25 0C,

16


BLANK PAGE

srjc promo 2009 paper 1

Documents