5.1.1-how fast

Question 1

what are the units for both average and instantaneous rate

Answer 1

moldm-3 s-1

Question 2

define average rate

Answer 2

rate over a range of time

Question 3

define instantaneous rate

Answer 3

rate at a precise point in time

Question 4

how can you calculate average rate

Answer 4

change in concentration/
change in time
rate is the change in concentration of a reactant or product over time.

Question 5

how do you calculate instantaneous rate

Answer 5

draw a tangent at that point and calculate the gradient

Question 6

what is a general rate equation

Answer 6

rate=K(A)^M (B)^N

Question 7

what are the units for concentration

Answer 7

mol dm-3

Question 8

what is K and what is is dependant on

Answer 8

rate constant
dependant on temperature
as temperature increases rate increases so K must increase

Question 9

finding units for k

Answer 9

in booklet

Question 10

draw concentration time-graph for formation of product

Answer 10

in booklet

Question 11

draw concentration time-graph for disappearing of reactant

Answer 11

in booklet

Question 12

what is a first order reactant

Answer 12

direct proportionality between concentration of reactant and rate of reaction
eg-as one doubles so will the other.

Question 13

draw the concentration-time graph for 1st order reactant

Answer 13

in booklet

Question 14

draw the rate-concentration graph for 1st order reactant

Answer 14

in booklet

Question 15

what is a 0th order reaction

Answer 15

no relationship between concentration of a reactant and rate of reaction

Question 16

draw the concentration time graph for a 0th order reaction

Answer 16

in booklet

Question 17

draw the rate-concentration graph for 0th order reactant

Answer 17

in booklet

Question 18

what is a 2nd order reaction

Answer 18

rate is proportional to the concentration of a reactant squared

Question 19

draw the rate-concentration graph for 2nd order reactant

Answer 19

in booklet

Question 20

how do you calculate the overall order of reaction

Answer 20

add up the powers

Question 21

define half-life

Answer 21

Time taken for the concentration of a reactant to fall to half its original value

Question 22

What is the half life of the first order reaction

Answer 22

Constant

Question 23

What is an intermediate

Answer 23

Does not appear in the overall equation as it is used up in late steps

Question 24

What is the rate determining step

Answer 24

Slowest step in a multistep reaction

Question 25

if the concentration of a reactant appears in the rate equation where else must it appear

Answer 25

If the concentration of a reactant appears in the rare equation then it must be involved in the rate determining step

Question 26

how to calculate rate constant in a graph

Answer 26

K=ln(2)/half life

Question 27

what happens to K (rate constant) as temperature increase

Answer 27

-as temperature increases
-K increases and Ea

Question 28

express the arrhenius equation in terms of y=mx +c

Answer 28

lnk=-Ea/R X 1/T + lnA

Question 29

what units does this answer have

Answer 29

jmol-1 to need to divide by 1000 to turn into kJmol-1