The ionization constant of chloroacetic acid is `1.35 × 10^(-3)`. What will be the pH of 0.1M acid and its 0.1M sodium salt solution?

Explanation

i. pH of acid solution: It is `W_(A)`
`pH_(W_(A))=1/2(pK_(a)-logC)`
`=1/2(2.86-log 0.1)=1.93`
ii. `K_(a)=1.35.5 10^(-3) pK_(a)=2.86`
Sodium acetate is a salt of `W_(A)//S_(B)`.
`pH=1/2 (pK_(w)+pK_(a)+log C)`
`=1/2(14+2.86+log 0.1)`
`=1/2(16.86-1)=7.94`