For a reaction `2NO(g) + 2H_2(g) to N_2(g) + 2H_2O(g)` , the following data were obtained.

Calculate the order of reaction.

Options

A. 1
B. 2
C. 0
D. 3

Explanation

Assuming rate law can be expressed as follows : rate `=k[NO]^x[H_2]^y`
By analysing the data :
From observations 1 and 2, we see that `[H_2]` is constant and when [NO] is tripled, the rate is also tripled.
`rArr "rate"(r ) prop[NO] rArr x = 1`
From observations 2 and 3, we see that [NO] is constant , when `[H_2]` is increased four times, the rate also increases four times.
`"rate" prop [H_2] rArr y = 1`
`rArr r = k [NO][H_2O]`
`rArr` The order of reaction w.r.t NO and `H_2` is 1 and the overall order of reaction is 1 + 1 = 2.