Chapter 14

Question 1

Particles must collide with one another. Only effective collisions result in product formation

Answer 1

Collision Theory

Question 2

• must have sufficient energy
• proper orientation

Answer 2

For an effective collision (collision theory)

Question 3

Reactions whose rate depends on the concentration of one of the reactants raise to the first power

Answer 3

First order reactions

Question 4

Reactions whose rate depends on the concentration of one the reactants raised to the second power, or on the product of the concentrations of two different reactants each raised to the first power

Answer 4

Second Order reactions

Question 5

reaction whose rate is independent of reactant concentration

Answer 5

Zeroth order Reaction

Question 6

Amount of time required for half of the reactant to disappear (i.e. time it takes for the reactant concentration to drop to half of its original value)

Answer 6

Half-life of reaction

Question 7

• most reactions occur in a series of steps
• the balanced equation does not tell us how the reaction occurs
• there are often a series of steps which add together to give the overall reaction

Answer 7

Reaction mechanisms

Question 8

1. Each elementary step has 1 or 2 reactants
2. elementary reactions add up to give the overall reaction
3. rate-determining step must have same rate law as the determined experimentally for overall reaction (first reaction should be the slowest step)

Answer 8

3 requirements to be a valid mechanisms

Question 9

step with the largest activation energy

Answer 9

Elementary step

Question 10

the slowest step in the mechanism

Answer 10

rate-determining step

Question 11

a substance that increases the rate of a chemical reaction without being used up itself

Answer 11

catalyst

Question 12

• acts by changing the reaction mechanism
• provides an alternate set of elementary steps with more favorable kinetics

Answer 12

Catalyst

Question 13

speeds up reaction by lowering activation energy

Answer 13

catalyst

Question 14

• heterogeneous
• homogenous
• enzyme

Answer 14

Types of catalysts

Question 15

reactants and catalyst are in different faces

Answer 15

heterogeneous catalyst

Question 16

catalyst often solid additive or surface

Answer 16

heterogeneous catalyst

Question 17

most important in industrial chemistry

Answer 17

heterogeneous catalyst

Question 18

used in catalytic converters in automobiles

Answer 18

heterogeneous catalyst

Question 19

• efficient catalytic converter serves two purposes:
  
  • oxidizes CO and unburned hydrocarbons into CO2 and H2O
  • converts NO and NO2 into N2 and O2

Answer 19

heterogeneous catalyst

Question 20

Reactants and catalysts are dispersed in single phase

Answer 20

Homogenous Catalyst

Question 21

biological catalyst

Answer 21

Enzyme catalysts