Question

Find the pH of a 5.0 x 10-1 mol L-1 solution of hydrocyanic acid. pKa(HCN) = 9.31.

Answer 1

find \([H^+]\) with and equilibrium expression (and an ICE table).

then use the relation \(pH=-log[H^+]\)

Answer 2

with an*

Answer 3

@aaronq explains it perfect.

Answer 4

oh.. um and is this a weak acid? and if this was a base I'd subtract it from 14?

Answer 5

No, it depends on if you are trying to find the [H+], if you were trying to find the [OH+], then you would.

Answer 6

yes.. that what i meant.. thank you alpha

Answer 7

@ecah1 They will never ask you it in that way, they will always ask you for the H, or OH, just saying :) <3

Answer 8

cool.. thnx