1.9 Rate equations

Question 1

2NO + Cl2 –> 2NOCl

Describe how you would use an inital rates method to determine that this reaction is in “x order” with respect to NO.

Answer 1

Stage 1:
- use different concs of NO
- keep the conc of Cl2 constant and in excess
- begin a timer when the reactants are mixed
- measure the conc of NO at regular time intervals

Stage 2:
- plot a graph of conc of NO (y axis) against time (x axis).
- draw a line of best fit
- draw a tangent to the line and find the gradient
- repeat for all inital concs of NO

Stage 3:
- record each inital conc of NO and its corresponding inital rate
- compare the data for two of the experimental runs
- confirm this result by using different pairs of the experimental runs.

Question 2

Write out all possible arrangements of the arrhenius equation

Answer 2

Equation for A is wrong.

it should be:
A = k/e^-Ea/RT

Question 3

link the arrhenius equation to a y=mx+c graph

Answer 3

y = mx + c
lnk = -Ea/RT + lnA