Question

Find the pH of 0.135M NaCN solution. For HCN, Ka=4.9⋅10−10

Answer 1

First, write the equilibrium expression and \(\sf \sf \color{red}{ K_b}\) reaction, NaCN is a weak base.

Answer 2

NaCN \(_{(aq)}\) \(\sf \rightleftharpoons\) HCN \(_{(aq)}\) + OH\(^-\)\(_{(aq)}\)