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Unit 3. Reactions
IV. Kinetics
Quiz 1


1.A reaction follows the rate law: Rate = k[A]2. Which of the following plots will give a straight line?
1/[A] versus 1/time
[A]2 versus time
1/[A] versus time
ln[A] versus time
[A] versus time

2.For the following reaction:

the rate law is Rate = k[NO2]2. If a small amount of gaseous carbon monoxide (CO), is added to a reaction mixture that was 0.10 molar in NO2 and 0.20 molar in CO, which of the following statements is true?
Both k and the reaction rate remain the same
Both k and the reaction rate increase
Both k and the reaction rate decrease
Only k increases, the reaction rate remains the same
Only the reaction rate increases, k remains the same

3.For the following reaction:

the rate law is Rate = k[H2][I2]. If a small amount of iodine vapor (I2), is added to a reaction mixture that was 0.10 molar in H2 and 0.20 molar in I2, which of the following statements is true?
Both k and the reaction rate decrease
Both k and the reaction rate increase
Both k and the reaction rate remain the same
Only k increases, the reaction rate remains the same
Only the rate increases, k remains the same

4.The specific rate constant, k, for radioactive beryllium-11 is 0.049 s-1. What mass of a 0.500 mg sample of beryllium-11 remains after 28 seconds?
0.250 mg
0.127 mg
0.0625 mg
0.375 mg
0.500 mg

5.The slow rate of a particular chemical reaction might be attributed to which of the following?
a low activation energy
a high activation energy
the presence of a catalyst
the temperature is high
the concentration of the reactants are high

6.
The above represents a proposed mechanism for the catalyzed oxidation of CO by O3. What are the overall products of the catalyzed reaction?
CO2 and O2
NO and CO2
NO2 and O2
NO and O2
NO2 and CO2

7.
The above represents a proposed mechanism for the hydrolysis of (CH3)3CBr. What are the overall products of the reaction?
(CH3)3C+ and Br-
(CH3)3COH2+ and H+
(CH3)3COH and H+
(CH3)3COH, H+, and Br-
H+ and Br-

8.The energy difference between the reactants and the transition state is
the free energy.
the heat of reaction.
the activation energy.
the kinetic energy.
the reaction energy.

9.Which of the following best describes the role of the spark from the spark plug in an automobile engine?
The spark decreases the energy of activation for the slow step.
The spark increases the concentration of the volatile reactant.
The spark supplies some of the energy of activation for the combustion reaction.
The spark provides a more favorable activated complex for the combustion reaction.
The spark provides the heat of vaporization for the volatile hydrocarbon.



10.The table above gives the initial concentrations and rate for three experiments.
The reaction is What is the rate law for this reaction?
Rate = k[ClO2]2[OH-]2
Rate = k[ClO2]
Rate = k[ClO2]2[OH-]
Rate = k[OH-]2
Rate = k[ClO2][OH-]