Page 159 - [B._MURPHY,_C._MURPHY,_B._HATHAWAY]_A_working_meth

Chemical Kinetics II 143
How many of the following statements are true?
* The reaction is second-order with respect to B.
* The reaction is third-order overall.
* The reaction is first-order with respect to A.
* A and B are consumed at the same rate in the reaction.
(a) 4 (b) 3 (c) 2 (4 1
2. If the half-life of the first-order decomposition of A at 34 "C is
2.05 x lo4 s, what is the value of the rate constant in s-'?
(a)2.05 x low4 (b) 1.03 x lo4 (c) 3.38 x (d) 3.38 x lo5
3. The rate constant doubles when the temperature is increased
from 35 to 53 "C. What is the activation energy of the reaction in
kJ mol-'? (R = 8.314 J K-' mol-').
(a) -3.2146 (b) 32146 (c) 0.594 (d) 32.146
4. A zero-order reaction A + Products commences with [&I =
0.25 M, and after 2 minutes [A] = 0.032 M. Determine k, the
rate constant for the reaction, in Ms-'.
(a) 0.109 (b) 0.0018 (c) -0,109 (d) 0.018
5. In the reaction 2A(,) + B,) + 2C(,) the following initial rates
were observed for certain reactant concentrations:
[AI/M [BI/M Initial rate/ M h-'
Rate 1 0.25 0.25 3.2
Rate 2 1 .oo 0.25 12.8
Rate 3 1 .oo 1 .oo 6.4
What is the rate equation for the reaction?
(a) Rate = k[A]o.SIB]l (b) Rate = k[A]'[B]-0.5
(c) Rate = k[A]'[B]0*5 (d) Rate = k[A]o*5[B]-'
6. For a second-order reaction, A + Products, what are the units of
k, the specific rate constant?
(a) (time)- ' (b) (cone.)-'.(time)-'
(c) (conc.).(time)-* (d) (conc.).(time)- '

LONG QUESTIONS ON CHAPTERS 8 AND 9
1. A reaction obeys the stoichiometric equation A + 2B + 2C.
Rates of formation of C at various concentrations of A and B are
given in the following table: