An acidic buffer contains equal concentrations of acid and salt. The dissociation constant of acid is ${10}^{-5}$. The pH of the buffer solution is

Given data: It is given to find out pH of a buffer solution which contains equal concentrations of acid and salt & the dissociation constant of acid is ${10}^{-5}$. 

Concept used:$p{K}_a=-log[K_a$, pH = $p{K}_a+log\frac{\left[salt\right]}{\left[acid\right]}$

Explanation: $p{K}_a=-log\left[K_a\right]$ = $-log\left[{10}^{-5}\right]$ = 5

pH =$p{K}_a+log\frac{\left[salt\right]}{\left[acid\right]}$

since [acid] = [salt]

= 5 + 0 = 5