RATE OF REACTION QUIZ Part II

1. For 2NO + O2 --> 2NO2 , initial rate data are:
[NO] 0.010 M; 0.010 M; 0.030 M
[O2 ] 0.010 M; 0.020 M; 0.020 M
rate 2.5; 5.0; 45.0 mM/sec
The rate law is Rate = k[O2 ]y and ....
a. x = 1 y = 2
b. x = 2 y = 1
c. x = 1 y = 1
d. x = 2 y = 2
e. none of these
2. A and B are mixed and the reaction is timed until a color change occurs. The data are:
[A] 0.100 M; 0.050 M; 0.100M
[B] 0.140 M; 0.140 M; 0.070M
time 25 sec; 50 sec; 100 sec
The order of the reaction in terms of [A] is ....
a. zero
b. second
c. half
d. first
e. none of these
3. If a reaction is first order with a rate constant of 5.48 x 10-2 sec-1, how long is required for 3/4 of the initial concentration of reactant to be used up?
a. 25.3 sec
b. 36.5 sec
c. 6.3 sec
d. 18.2 sec
e. none of these
4. The rate of a specific chemical reaction is independent of the concentrations of the reactants. Thus the reaction is ....
a. first order
b. second order
c. exothermic
d. catalyzed
e. none of these
5. The following rate data were obtained at 20oC for the reaction of hemoglobin (Hb) carbon monoxide reaction. What is the rate-law expression for this reaction:
4 Hb + 3 CO --> Hb4(CO)3
Exp. [Hb] mol/L; [CO] mol/L; Rate of disappearance of Hb (M/sec)
1 - 3.36 x 10-6; 1.00 x 10-6; 9.41 x 105
2 - 6.72 x 10-6; 1.00 x 10-6; 1.88 x 106
3 - 6.72 x 10-6; 2.00 x 10-6; 3.76 x 106
a. rate = k[Hb]4[CO]3
b. rate = k[Hb]2 [CO]2
c. rate = k[Hb] [CO]
d. rate = k[Hb]
e. rate = k[Hb] [CO]2
6. The following rate data were obtained at 25oC for the indicated reaction. What is the rate-law expression for the reaction:
A + B --> 2 C?
Exp. [A] mol/L; [B] mol/L; te of formation of C (M/min)
1 - 0; 10; 0 x 10-4
2 - 0; 30; 2 x 10-2
3 - 0; 30; 6 x 10-3
4 - 0; 20; 4 x 10-3
a. rate = k[A] [B]
b. rate = k[A] [B]2
c. rate = k[A]2 [B]2
d. rate = k[B]
e. rate = k[A]2[B]
7. The following rate data were obtained at 25oC for the indicated reaction. What is the rate-law expression for the reaction:
2 A + B --> ?
Exp [A] mol/L; [B] mol/L; Rate of formation of C (M/min)
1 - 0.10; 0.10; 2.0 x 10-4
2 - 0.20; 0.10; 8.0 x 10-4
3 - 0.40; 0.20; 2.6 x 10-2
a. rate = k[A]2 [B]2
b. rate = k[A] [B]
c. rate = k[A]2[B]3
d. rate = k[A] [B]2
e. rate = k[A]2[B]
8. The following rate data were obtained at 25oC for the indicated reaction. What is the rate-law expression for the reaction:
2 A + B --> 3 C?
Exp. [A] mol/L; [B] mol/L; Rate of formation of C (M/min)
1 - 0.10; 0.10; 4.0 x 10-4
2 - 0.30; 0.30; 1.2 x 10-3
3 - 0.10; 0.30; 4.0 x 10-4
4 - 0.20; 0.40; 8.0 x 10-4
a. rate = k[A]
b. rate = k[A] [B]
c. rate = k[A] [B]2
d. rate = k[A]2[B]
e. rate = k[B]
9. The decomposition of N2O5(g) à NO2(g) + NO3(g) proceeds as a first order reaction with a half-life of 30.0 seconds at a certain temperature. If the initial concentration [N2O5]0 = 0.400 M, what is the concentration after 120 seconds?
a. 0.000 M
b. 0.100 M
c. 0.025 M
d. 0.200 M
e. 0.050 M
10. What is the rate constant of the reaction in the above Problem ?
a. 2.31 x 10-2 s-1
b. 2.31 x 10-1 s-1
c. 20.7 s-1
d. 30.0 s-1
e. 43.3 s-1