Physical Chemistry Problems. ©Mike Lyons 2013.
JF Chemistry Module CH1101. 2009
MCQ Semister 1 Test
1. Consider the synthesis of ammonia which proceeds according to the
following reaction: ½ N2(g) + 3/2 H2(g) NH3(g) . If the standard
change in Gibbs energy for the reaction is given by ∆rG0 = - 16,370
J mol-1 at T = 298 K then the equilibrium constant K for the
reaction is:
(a) 7.38 x 102 (Answer)
(b) 7.38 x 10-2
(c) 0.1
(d) 100
(e) there is insufficient data supplied to answer the question.
You may assume that the gas constant R = 8.314 J mol-1
K-1
.
2. In air at 298 K which gas has the lowest average root mean square
speed?
(a) H2O(g) ; (b) CO2(g) (Answer) ; (c) CO(g) ; (d) Ne(g) ; (e)
CH4(g).
3. For ideal gases which of the following statements are correct?
i. At constant temperature, the volume of a fixed mass of gas
is proportional to the external pressure.
ii. At constant external pressure and temperature, when 1L of
N2 reacts with 2L of O2, 2L of NO2 are formed
iii. At a given temperature and external pressure, equal volumes
of any ideal gas contain the same number of molecules
iv. At a given temperature, the molecules in any ideal gas have
the same average velocity
v. At a given pressure and temperature, the mean-free path of
a gas is independent of the volume of the containing vessel
a) (ii) and (iii)
b) (i), (iii) and (v)
c) (ii) and (iii)
Physical Chemistry Problems. ©Mike Lyons 2013.
d) (ii) and (v)
e) (ii), (iii) and (v) (Answer)