7A.11( part b)

[kennedyp]

For part b I'm a bit confused. The book states that the reaction rate increases by a factor of 2 if H2 is doubled, however I remember the book saying that if you have a second order reaction and double the reactant, the rate increases by a factor of 4. PLease help!

[sbeall_1C]

Hi!

For this question, the overall reaction is second order, but each individual reactant is first order. Therefore, doubling the concentration of H2 will only double the rate or reaction. You are right that if H2 were by itself second order, it would quadruple the rate; however, the order of reaction for H2 is only first order, and the overall rate is second.