Question

The pH of a buffer solution containing 0.2 mole per litre `CH_(3)COONa` and 1.5 mole per litre `CH_(3)COOH` is (`K_(a)` for acetic acid is `1.8 xx 10^(-5)`)
A. 4.87
B. 5.8
C. 2.4
D. 9.2

Answer 1

Correct Answer - A
`pH = -log K_(a) + log.(["Salt"])/(["Acid"])`
`= log [1.8 xx 10^(-5)] + log.(0.2)/(1.5) = 4.87`.