Reaction Rates
Practice Test
1.
What is the name given to a catalyst that exists in the same physical state as the reaction being catalyzed?
a.
homogeneous catalyst
b.
solid-state catalyst
c.
heterogeneous catalyst
d.
ephemiral catalyst
2.
What is the name given to a chemical produced in one elementary step and used up in a subsequent elementary step?
a.
intermediate
b.
reaction mechanism
c.
complex step
d.
elementary step
3.
In the rate-law expression, Rate =
k
A
, what does the symbol
k
represent?
a.
concentration
b.
instantaneous rate
c.
reaction order
d.
specific rate constant
4.
What are the individual steps in a complex reaction known as?
a.
rate-determining steps
b.
elementary steps
c.
complex steps
d.
intermediate steps
5.
What is the reaction order for each reactant in the following rate-law expression? Rate = k
A
B
2
C
3
a.
first order for A, first order for B, first order for C
b.
first order for A, second order for B, second order for C
c.
first order for A, second order for B, first order for C
d.
first order for A, second order for B, third order for C
6.
What is the term used to describe the minimum energy needed to form an activated complex?
SC.B.1.4.1
a.
kinetic energy
b.
potential energy
c.
temperature
d.
activation energy
7.
What happens to the activation energy of the reaction when a catalyst is present?
SC.B.2.4.1
a.
The activation energy decreases.
b.
The activation energy increases.
c.
The activation energy does not change.
d.
The reaction stops.
8.
When the concentration of a reactant is increased, the _______________.
SC.A.1.4.4
a.
reaction slows down
b.
reaction stops
c.
reaction rate does not change
d.
reaction speeds up
9.
What is the most common experimental method for evaluating a reaction order called?
SC.H.1.4.1
a.
method of final rates
b.
method of instantaneous rates
c.
method of initial rates
d.
method of experimental rates
10.
How are the rate law and the order for a complex reaction determined?
SC.H.1.4.1
a.
by calculation
b.
by estimation
c.
by trial and error
d.
by experimentation
11.
What quantity is defined by the change in concentration of a component in a chemical reaction divided by the change in time of the reaction?
SC.A.1.4.4
a.
rate order
b.
specific rate constant
c.
instantaneous rate
d.
catalyst
12.
How much time has passed when 5 mol/L have reacted at an average rate of 0.5 mol/L·s?
a.
1.0 s
b.
10 s
c.
0.1 s
d.
100 s
13.
What is the instantaneous rate for a reaction that is second order in A and first order in B when
A
= 2
M
and
B
= 3
M
? The specific rate constant for the reaction is 0.1
M
-2s-1.
SC.A.1.4.4
a.
0.012
M
/s
b.
12
M
/s
c.
0.12
M
/s
d.
1.2
M
/s
14.
What is the slowest of the elementary steps in a complex reaction called?
SC.A.1.4.4
a.
propagating step
b.
mechanism
c.
fast step
d.
rate-limiting step
15.
What is the overall reaction order for the following rate-law expression? Rate = k
A
B
2
C
3
a.
6
b.
7
c.
5
d.
4
16.
Use the data in the table to determine how long it will take to completely consume 1L of 1M butyl chloride
C
4
H
9
Cl
, assuming the same reaction rate.
Molar Concentration of
C
4
H
9
Cl
C
4
H
9
Cl
at t= 0.00 s
C
4
H
9
Cl
at t= 4.00 s
0.220M
0.100M
SC.A.1.4.4
a.
0.300 s
b.
0.0300 s
c.
33.3 s
d.
3.00 s
17.
A substance that speeds up the reaction rate but is not consumed in the reaction is a
n
____________.
SC.A.1.4.4
a.
inhibitor
b.
product
c.
reactant
d.
catalyst
18.
Automobiles use a catalytic converter made of metal to ensure complete combustion of gasoline. What type of catalyst is present in automobiles?
a.
solid-state catalyst
b.
heterogeneous catalyst
c.
homogeneous catalyst
d.
ephemiral catalyst
19.
Use the data in the table to calculate the average reaction rate expressed in moles Cl
2
consumed per liter per second.
Time
s
H
2
M
Cl
2
M
HCl
M
0
0.03
0.05
0.55
10
0.005
0.025
0.05
SC.A.1.4.4
a.
0.002 mol/
L s
b.
0.003 mol/
L s
c.
0.0025 mol/
L s
d.
0.030 mol/
L s
20.
What Greek symbol is used to represent change?
a.
→
b.
∈
c.
Δ
d.
Σ
