5 Written questions
5 Matching questions
- Compounds A and B react to form C and D in a reaction that is found to be second-order overall and second-order in B. The rate constant at 30°C is 0.622 liter per mole per minute.
A + B → C + D
How many minutes does it take 4.0 × 10−2 M B (mixed with excess A) to be reduced to 3.3 × 10−2 M B?
a. 1.4 min
b. 3.6 min
c. 5.0 min
d. 6.4 min
e. 8.5 min
- Which of the following reactions would be expected to be the slowest?
a. Ag+(aq) + Cl−(aq) → AgCl(s)
b. H+(aq) + OH−(aq) → H2O
c. CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
d. Pb2+(aq) + CrO42−(aq) → PbCrO4(s)
e. H+(aq) + CN−(aq) → HCN(aq)
- The decomposition of dinitrogen pentoxide obeys the rate-law expression rate = 0.080 min−1[N2O5]. If the initial concentration of N2O5 is 0.30 M, what is the concentration after 2.6 minutes?
N2O5 → N2O3 + O2
a. 0.38 M
b. 0.028 M
c. 0.24 M
d. 0.13 M
e. 0.32 M
- The specific rate constant, k, for a reaction is 0.44 s−1 at 298 K, and the activation energy is 245.kJ/mol. Calculate k at 398 K. (The universal gas constant = 8.314 J/mol•K.)
a. 2.71 × 1010 s−1
b. 6.17 × 1010 s−1
c. 1.03 × 1010 s−1
d. 8.32 × 108 s−1
e. 4.51 × 109 s−1
- Consider the hypothetical reaction shown below.
A + 2B → AB2
Assume that the following proposed mechanism is consistent with the rate data.
B + B → B2 slow
B2 + A → AB + B fast
B + AB → AB2 fast
A + 2B → AB2 overall
Which one of the following statements must be true? The reaction is ____.
a. first order in A, second order in B, and third order overall
b. second order in B and second order overall
c. first order in A and first order overall
d. second order in B, zero order in A, and third order overall
e. second order in A and second order overall
- a e. 8.5 min
- b a. 2.71 × 1010 s−1
- c c. 0.24 M
- d b. second order in B and second order overall
- e c. CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
5 Multiple choice questions
- go to graph
- b. The rate is reduced by 3/4.
- a. decrease by 3/4
- b. 54.5 s−1
- c. Each enzyme catalyzes many different reactions in a living system.
5 True/False questions
The following data were collected for the following reaction at a particular temperature. What is the rate-law expression for this reaction? rate = ____.
A + B → C
Experiment Initial [A] Initial [B] Initial Rate of Formation of C
1 0.10 M 0.10 M 4.0 × 10−4 M/min
2 0.20 M 0.20 M 3.2 × 10−3 M/min
3 0.10 M 0.20 M 1.6 × 10−3 M/min
e. k[A][B]2 → d. k[H2][CO]
What would be the activation energy of a reaction if its rate constant at 35°C was double the value of its rate constant at 25°C?
a. 63.8 kJ/mol
b. 75.1 kJ/mol
c. 8.12 kJ/mol
d. 52.9 kJ/mol
e. 68.3 J/mol → d. 47.1 kJ/mol
A plot of versus time is linear for the reaction D → E. What is the kinetic order of the reaction?
e. negative one → a. second
124 go to graph → graph
One of the reactions that is used to produce gaseous hydrogen commercially follows. A proper expression for the rate of this reaction could be ____.
H2O(g) + CO(g) → H2(g) + CO2(g)
e. → c. is third.