The `pH` of a dilute solution of acetic acid wea found to be `4.3`. The addition of a small crystal of sodium acetate will cause `pH` to

Options

A. Become less than `4.3`
B. Beome more than `4.3`
C. Remain equal to `4.3`
D. Unpredictable

Answer

B

Explanation

`CH_(3)COOH rarr CH_(3)COO^(Theta) +H^(o+)`
`CH_(3)COONa rarr CH_(3)COO^(Theta) +Na^(o+)`
Due to common ion `(CH_(3)COO^(Theta))`, the supression of ionisation of `CH_(3)COOH` takes place, so the concentration of `H^(o+)` decreases, so `pH` increases. So `pH` must be more than `4.3`.