NANYANG TECHNOLOGICAL UNIVERSITY
SINGAPORE
ENTRANCE EXAMINATION
CHEMISTRY (Sample)
Time Allowed : 2 hours
INSTRUCTIONS
1.
This paper consists of TWO (2) Sections and comprises SIX (6) pages.
2.
Answer ALL the questions in Section A and Section B.
3.
For Section A, each multiple choice question carries 2 marks. For Section B, each
question carries 15 marks.
4.
Answers for Section A must be submitted on the answer sheet provided.
SECTION A
This section consists of TWENTY (20) multiple choice questions. Answer ALL questions in
this section. Indicate your answers on the answer sheet provided.
1.
Which of the following has no permanent dipole moments?
a.
b.
c.
d.
2.
Which is the most abundant element in the universe?
a.
b.
c.
d.
3.
CHCl3
CH2Cl2
C2Cl4
C2HCl3
Hydrogen
Helium
Carbon
Oxygen
Which one of the following equilibrium mixture will not be affected by a change in
pressure?
a.
b.
c.
d.
CH3CH2CH2OH(g)
CH3CH=CH2(g) + H2O(g)
BaCO3(s)
BaO(s) + CO2(g)
H2(g) + Cl2(g)
2HCl(g)
O2(g) + 2Hg(l)
2HgO(s)
1
4.
Calcium with elemental chlorine yields calcium chloride. Write a balanced chemical
equation for this reaction.
a.
b.
c.
d.
5.
On heating, 0.09 mole of an element M reacts with 0.135 mole of oxygen gas. The empirical
formula of the oxide of M is
a.
b.
c.
d.
6.
1s22s22p63s23p63d34s2
1s22s22p63s23p63d6
1s22s22p63s23p63d5
1s22s22p63s23p63d64s2
A microwave oven emits radiation at a wavelength of 0.500 cm. What is the frequency of
this radiation?
a.
b.
c.
d.
9.
-57.7 kJ
+714.3 kJ
0 kJ
+57.7 kJ
Iron has a atomic number of 26. What is the electron configuration of the iron in FeCl3?
a.
b.
c.
d.
8.
M2O2
M3O2
M4O6
M2O3
Given that ΔH0f (FeCl2(s)) = -341.8 kJ/mol and that ΔH0f (FeCl3(s)) = -399.5 kJ/mol, what is
ΔHrxn for the reaction: FeCl2(s) + ½ Cl2(g) →FeCl3(s)
a.
b.
c.
d.
7.
Ca(s) + Cl2(g) → CaCl(s) + Cl(g)
Ca(s) + Cl2(g) → CaCl2(s)
Ca(s) + 2 Cl2(g) → CaCl4(s)
2 Ca(s) + Cl2(g) → 2 CaCl(s)
1.67  10-11 s-1
6.67  10-7 s-1
6.00  1010 s-1
2.00 s-1
The radioactive decay of sodium-24 has a half-life of 14.66 hours. How many grams of the
radioactive sodium-24 will be left after 73 hours if the initial weight of the sample is 4g?
a.
b.
c.
d.
0.125g
0.032g
0.064g
0.26g
2
10. Use the following information to answer the question below:
Sn2+(aq) + 2e
Sn(s)
E0 = -0.14 V
Sn4+(aq) + 2e
Sn2+(s)
E0 = +0.15 V
Fe2+(aq) + 2e
Fe(s)
E0 = -0.44 V
Fe3+(aq) + e
Fe2+(aq)
E0 = +0.77 V
Under standard conditions, which of the following statements is correct?
a.
b.
c.
d.
Sn(s) can reduce Fe(s)
Fe(s) can oxidize Sn2+(aq)
Sn2+(aq) can reduce Fe3+(aq)
Fe3+(aq) can reduce Sn4+(aq)
11. What is the pH of a solution of HNO3 with a concentration of 0.0013M?
a.
b.
c.
d.
2.89
6.64
1.30
11.10
12. The maximum number of electrons in the shell having the principle quantum number of n =
3 is
a.
b.
c.
d.
18
26
28
36
13. The hybridization of the nitrogen atom in the molecule NF3 is
a.
b.
c.
d.
sp2
spd
sp3
sp3d
14. Which of the following statements is true about the elements in Group II of the Periodic
Table?
a.
b.
c.
d.
The ionic radius decreases down the group
The electronegativity decreases down the group
They form stable oxidation states of two and four
The atomic radius increases down the group
3
15. The oxidation number of Chromium in the ion CrO42a.
b.
c.
d.
+4
+7
+6
+3
16. Which of the following compounds would react most rapidlywith NaCN?
a.
b.
c.
d.
1-bromobutane
(R)-2-bromobutane
(S)-2-bromobutane
1-bromo-2-methylpropane
17. The following reaction can be classified as
O
O
a.
b.
c.
d.
200°C
+ CH3CO2H
CH3
eminination
substitution
oxidation
rearrangement
18. Reaction of benzene with benzoyl chloride and aluminium trichloride will give as the
product:
a.
b.
c.
d.
benzophenone
chlorobenzene
no reaction
benzoic acid
19. What will be the product(s) of the following reaction:
Br
Br
NaOMe,
MeOH,
20°C
OMe
MeO
(iii) only
(ii) only
(i) and (ii)
(i), (ii) and (iii)
4
OMe
Br
(ii)
(i)
a.
b.
c.
d.
Br
MeO
(iii)
20. What will be the product(s) of the following reaction
KOH, EtOH, 80°C
OH
(i)
Br
a.
b.
c.
d.
(ii)
(iii)
(i) only
(ii) only
(ii) and (iii)
(iii) only
SECTION B
This section consists of FOUR (4) questions. Answer ALL questions in this section.
1. (a) Using dots to represent electrons, draw the electron distribution diagram (Lewis
structure) of ClF3. Use Valence Shell Electron Pair Repulsion theory (VSEPR) to explain the
shape of this molecule.
(b) Draw and label all the valence orbitals found in chlorine atom.
2. Data for the reaction 2 NO(g) + O2(g)  2 NO2 (g) are given in the table.
Experiment
1
2
3
4
Concentration (mol/L)
[NO]
[O2]
-4
3.6×10
5.2×10-3
-4
3.6×10
1.04×10-2
1.8×10-4
1.04×10-2
1.8×10-4
5.2×10-3
Initial Rate
(mol/L ∙ h)
3.4×10-8
6.8×10-8
1.7×10-8
?
(a) Determine the rate constant and write down the rate equation for the above
(b) What is the initial rate of the reaction in experiment 4?
5
reaction.
3. Lidocaine, a local anaesthetic, can be produced by the following sequence of reactions:
O
NH2
H3C
O
CH3
HN
Cl
Cl
O
Cl
H3C
CH3 (C2H5)2NH H3C
HN
N(C2H5)2
CH3
(a) To achieve a high yield, what additional kind of reagent must be added in step 1? Briefly
explain your answer.
(b) Esters can be made by acid catalysis. Explain whether the product of step 1 can be made
by heating 2,5-dimethylaniline with chloroacetic acid in the presence of some sulfuric
acid as a catalyst.
(c) Assuming that step 2 is run at a concentration of 1 M with respect to both reactants,
explain the effect on the reaction rate of changing the concentration to 0.5 M.
4. (a) Discuss the difference in reactivity between the following pairs of compounds under the
conditions given
(i) benzene and phenol with bromine
(ii) 1-hexanol and 2-hexanol with chromium trioxide in acid
(iii) ethylamine and acetamide with dilute hydrochloric acid
(iv) sodium methoxide and sodium t-butoxide with 1-bromopropane
(b) How would you carry out the following transformation? More than one step may be
required.
OH
OH
O
- END OF PAPER -
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