The suggested timefor this section is 1.5 hours.

Note: a table of selectedphysical constants etc. are given in Appendix 1, and standard reduction potentials are given in Appendix 2 and the Periodic Table in Appendix 3.

Question A1.

Which one of the following is CORRECT?

For a zero-order reaction         For a third-order reaction

A.

B.

C.

D.

E.

Question A2.

k has units of M s- 1

k has units of M s- 1

k has units of M- 1s- 1

k has units of s- 1

k has units of M- 1 s- 1

k has units of M- 1s- 1

k has units of M-2s- 1

k has units of M-2s- 1

k has units of M- 1s- 1

k has units of s- 1

(2 marks)

The kinetics of oxidation of bromide by bromate in acidic solution:

BrO3− + 5Br− +  6H+     ®  3Br2   +  3H2O

has a rate law that is given by kobs [BrO3− ] [Br− ] [H+]2 .

If an experiment is carried out in a highly acidic solution with a large excess of bromide over

bromate, the observed changes in bromine concentration with time are likely to conform to an integrated rate equation which is:

A.     zeroeth order

B.     first order

C.     second order

D.     third order

E.      fourth order

(2 marks)

Question A3.

The hydrolysis of sucrose to glucose and fructose is described by the reaction below: C12H22O11   +  H2O    ®    C6H12O6    +  C6H12O11

The activation energy for this reaction is 108 kJ mol- 1 .  If at 35 oC, k for this reaction is 6.2 × 10-5 s- 1, what is the rate constant, k, at 45 oC closest to?

A.     9.7 x 10-5 s- 1

B.     0.7 x 10-4 s- 1

C.      1.7 x 10-4 s- 1

D.     2.3 x 10-4 s- 1

E.      3.2 x 10-4 s- 1

(2 marks)

Question A4.

For a reaction at 500 °C, the rate constant is 570 s- 1 .  What is the half-life of the reaction at this temperature when the initial concentration of reactant, [A]0 = 0.2 M?

A.     836 s

B.     285 s

C.      8.8 × 10-3 s

D.      1.2 × 10-3 s

E.     None of the above

(2 marks)

Question A5.

At elevated temperatures, HI reacts according to the chemical equation:

HI(g) ® ½H2(g) + ½I2(g)

At 445 °C, the rate of reaction increases with concentration of HI as follows:

Rate (mol L-1 s-1) 7.5×10-4                        3.0×10-3                        1.2×10-2

[HI] (mol L-1) 0.005 0.010 0.020 What is the order of the reaction with respect to HI?

A.   ½                 B.   1                  C.   2                  D.   3                  E.   4

(3 marks)

Question A6.

The reduction of NO to N2 by hydrogen is proposed to have a mechanism involving the following elementary steps:

2NO  ® N2O2

N2O2   +  H2   ® N2O  +  H2O

N2O  +  H2   ® N2   +  H2O

In the overall stoichiometric reaction, at any time t,

A.     d[NO]/dt = d[H2O]/dt = 2d[N2]/dt

B.     d[N2O]/dt = d[N2]/dt = −d[H2]/dt

C.     d[H2O]/dt = d[N2]/dt = d[N2O2]/dt

D.     d[NO]/dt = d[N2]/dt = d[N2O]/dt

E. −d[NO]/dt = 2d[N2]/dt = −d[H2]/dt

(2 marks)

Question A7.

The following concentration/time data were determined at 120 oC for the breakdown of benzoyl peroxide, a radical initiator in some free radical polymerisation chain reactions.

Time (min)	0	15	30	45	60	75
[Benzoyl peroxide] × 102 (M)	2.19	1.53	1.09	0.77	0.54	0.38

The rate constant for this reaction is:

A.      1.38 min- 1

B.     0.032 min- 1

C.     5.3 x 10-4 s- 1

D.     3.8 x 10-4 s- 1

E.      Cannot be determined from this data.

(2 marks)

For Questions A8 – A10 consider the following structures I – IV:

HO        CH3

I

Br

II

CHO

III

CH3

IV

Question A8.

Which one of the above compounds would be expected to display four (4) peaks in its 13C NMR spectrum?

A.   I

Question A9.

B.   II only        C.    II and III only         D.   III only        E.   I, III and IV only (2 minutes)

Which one of the above compounds would be expected to display five (4) peaks in its 1H NMR spectrum?

A.   III only        B.   I and IV     C.    II and        D.   II only          E.   None of them only                   III only

(2 minutes)

Question A10.

Which one of the above compounds would be expected to display a strong absorption band in its infra-red (IR) spectrum close to 1700 cm- 1?

C.    III              D.   IV

Question A11.

O       O

O

H3C

H3C O

H3C

B

The strongest nucleophile in the list provided above is:

A.  Compound A

B.  Compound B

C.  Compound C

D.  Compound D

E.  None of the above (the are all equally strong).

(2 marks)

The following scheme is referred to in questions A12 – A15.

NH2 aniline

step 1

O HN

CH3

step 2

O HN NO2

CH3

O HN CH3 OH paracetamol

Question A12.

Part of a synthesis of the analgesic compound, paracetamol, is given above.  The most appropriate reagent to effect the transformation depicted in step 1 shown above is:

A.     acetic acid (ethanoic acid)

B.     ethyl acetate (ethyl ethanoate)

C.     acetic anhydride (ethanoic anhydride)

D.     acetone (propanone)

E.     None of the above.

(2 marks)

Question A13.

The type of reaction shown in step 1 of the scheme shown above is:

A.     an SN2 reaction

B.     an E1 reaction

C.     a nucleophilic addition reaction

D.     a nucleophilic addition/elimination reaction

E.     None of the above.

(2 marks)

Question A14.

The most appropriate reagent to effect the transformation depicted in step 2 of the sequence depicted above is:

A.     NO2 gas

B.     HNO3

C.     HNO3/H2 SO4

D.     NO3

E.     None of the above.

(2 marks)

Question A15.

The type of reaction shown in step 2 of the scheme shown above is:

A.     a nucleophilic aromatic substitution

B.     an electrophilic aromatic substitution

C.     a nucleophilic addition/elimination reaction

D.     an electrophilic elimination reaction

E.      None of the above.

(2 marks)

Question A16. E

Benzyl acetate, CH3CO2CH2C6H5, gives the characteristic flowery aroma to jasmine. Which sequence of reagents provides a plausible series of steps for the synthesis of benzyl acetate  from benzyl bromide (C6H5CH2Br):

NaOH(aq)     C2H5COCl

NaOH(aq)      CH3CH2OH, H+

NaOH(aq)     CH3CH2Cl

NaOH(aq) KMnO4 CH3CH2OH, H+

NaOH(aq)      CH3COCl

(3 minutes)

Question A17.

Which one of the compounds listed below would be expected to react the fastest in an SN2 reaction with sodium bromide?

A.     methanol

B.     2-iodobutane

C.     2-methyl-2-iodobutane

D.     sodium iodide

E.     None of the above would react with sodium bromide.

(2 marks)

OH

HCl

Cl

Which one of the following mechanisms most correctly describes the transformation depicted

above?

.

.

.

.

H

OH

H

OH

H

OH

H

OH

O

H2

Cl

Cl

H2 O H2