Rates of reaction

Question 1

Rate of reaction

Answer 1

1. Change in mass or concentration
2. of reactant or product
3. per unit time

Question 2

Order of reaction

Answer 2

the power to which a concentration is raised in the rate equation

Question 3

First order

Answer 3

concentration of reagent increases the rate proportionately

Question 4

Second order

Answer 4

rate is proportional to square of concentration of reagent

Question 5

zero order

Answer 5

increasing concentration of reagent has no effect on rate

Question 6

rate equation(+units)

Answer 6

rate = k[a]^a moldm^-3s^-1

Question 7

Rate constant

Answer 7

k is constant of proportionality
units s^-1

Question 8

half life

Answer 8

time taken for concentration of one reactants to fall by half

Question 9

Rate equation from rds

Answer 9

reactants (+conc) in rds or before will be used in rate equation

Question 10

Arrhenius equation

Answer 10

k = Ae^-Ea/RT
lnk = lnA + (-Ea/RT)

Question 11

Increased temperature (in Arrhenius)

Answer 11

rate constant increases
so rate of reaction increases

Question 12

Increase Ea in arrhenius

Answer 12

rate constant decreases
(less molecules exceed Ea)
rate of reaction decreases

Question 13

Arrhenius straight line

Answer 13

y = lnk
m= -Ea/R
x = 1/T
c= lnA

Question 14

Rate determining step

Answer 14

1. slowest step
2. highest activation energy
3. controls rate of reaction

Question 15

R-C graph 1st order

Answer 15

1. straight diagonal line
2. through origin
3. rate proportional to concentration

Question 16

R-C graph 2nd order

Answer 16

1. curve
2. through oririgin

Question 17

R-C zero order

Answer 17

1. straight horizontal line
2. not through origin

Question 18

C-T graph 1st order

Answer 18

1. curve
2. equal half lives

Question 19

C-T graph zero order

Answer 19

1. straight line
2. decreases

Question 20

C-T graph 2nd order

Answer 20

1. curve
2. unequal half lives

Question 21

Rate constant from 1st order

Answer 21

k = ln2/ half life

Question 22

Affect of temperature

Answer 22

1. more particles exceed activation energy
2. rate increases
3. k increases

Question 23

Catalyst

Answer 23

1. increases rate of reaction
2. lowers activation energy
3. more molecules exceed
4. increased chance of successful collisions

Question 24

Draw the botlzman graph

Question 25

Dynamic equilibrium

Answer 25

1. rate of forwards reaction equals rate of backwards reaction
2. concentration of products and reactants remain unchanged

Question 26

Pressure on kP

Answer 26

1. equilibirum position shifts
2. denominator of kP expression decreases/increases more than numerator
3. ratio decreases/ increases to restore kp