Why don't we write concentration ofH plus in numerator
Ques-exercise ques 3.5 4th part

Dear student,
As the question is not visible but we will try to help you 
if the reaction is supposed to be  $H^{+ }+B{r}^{-} \iff HBr$ then, in this case, H⁺ and Br^- will be in the denominator if the reaction is reversed then both of them will be in the numerator.

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