Chapter 45

Question 1

What factors affect the rate of the rxn?

Answer 1

1. Concentration
2. Temperature
3. Catalyst

Question 2

deltaH<0

exo or endo?

Answer 2

exo

Question 3

deltaH>0

exo or endo?

Answer 3

endo

Question 4

activation energy

Answer 4

minimum energy needed to start a rxn (to get to act. complex)

Question 5

Which reactions are reversible: endo or exo?

Answer 5

edno rxn are reversible; exo rxn are not reversible bc of the activation energy needed

Question 6

catalyst

Answer 6

lowers act. energy; speeds up rxn; mainly added to endo rxns

reactant of one step, prod in another

Question 7

reaction mechanism

Answer 7

step wise pathway that describes HOW reactants are converted into products; each step is elementary steps

Question 8

unimolecular

Answer 8

A –> product

Question 9

bimolecular

Answer 9

2A –> product or A + B –> prod

Question 10

termolecular

Answer 10

A + A + B –> product

Question 11

intermediate

Answer 11

product in one step, reactant in the next step

Question 12

homogeneous catalysis

Answer 12

reactants and catalyst in the same phase

Question 13

heterogeneous catalysis

Answer 13

reactants and catalysts in different phase

Question 14

rates at equilibrium

Answer 14

opp rates are equal

Question 15

act. complex

Answer 15

whats formed from collision of reactant molecules; the microsecond in time A&B collided successfully

Question 16

first order rxn

Answer 16

A –> product
rate = k[A]
slope = -k

Question 17

half life for first order rxn

Answer 17

ln 2/k

Question 18

second order rxn

Answer 18

A –> product

rate = k[A]^2

Question 19

zero order rxn

Answer 19

A –> product

rate = k

Question 20

What is the rate determining step (RDS)?

Answer 20

slowest step, overall rate depends on this step, sets pace for whole rxn

Question 21

the longer the time……

Answer 21

….the more stable the reactant

Question 22

reactions occur by themselves bc…..

Answer 22

they want to become more stable

Question 23

what helps make collisions more effective?

Answer 23

heat

Question 24

Graph of Ea: what is the top of the hump?

Answer 24

transition state

Question 25

the higher the act. energy

Answer 25

reactants less stability

Question 26

the more stable the reactants….

Answer 26

…..the less stable the product