Question

Catalytic decomposition of nitrous oxide by gold at `900^(@)C` at an initial pressure of 200mm was `50%` in 53 minutes and `73%` in 100 minutes.
(a) What is theorder of reaction?
(b) How much it will decompose in 100 minutes at the same temperature but at an initial pressure of 600mm?

Answer 1

(a) Using first order kintetic equation and substituting given values
In first case: `k=(2.303)/(53)log_(10).(200)/(200-100)=0.0131"min"^(-1)`

In second case `k=(2.303)/(100)log_(10).(200)/(200-146)=0.0131"min"^(-1)`
As the values of k come out to be the same in both cases, the reaction is of first order.
(b) As in the first order reaction, the time required for the completion of same fraction is independent of initial concentration, the percantage decomposition in 100 minutes when the initial pressure is 600 mm will aslo be `73%`