Question

why k2>k1 when delta H positive

Answer 1

when ∆H is positive it means it is endothermic reaction.

Means product is at a high potential energy than reactant,for which the reactant requires energy and the resultant reaction is endothermic.

So as you did not say the meaning of K1 and K2 I can not say about them.

Only remember ∆H is positive means endothermic reaction.

Thanks.
Tripathy