The expression to calculate pH of sodium acetate solution at `25^(@)C` is

Options

A. `pH = 7 + (1)/(2)pK_(b)(CH_(3)COOH) - (1)/(2)` log [salt]
B. `pH = 7 + (1)/(2)pK_(a)(CH_(3)COOH) - (1)/(2)` log [salt]
C. `pH = 7 + (1)/(2)pK_(b)(CH_(3)COOH) + (1)/(2)` log [salt]
D. `pH = 7 + (1)/(2)pK_(a)(CH_(3)COOH) + (1)/(2)` log [salt]

Answer

D

Explanation

pH of salt of `W_(A)//S_(B)` is `pH = (1)/(2)(pK_(w) + pK_(a) + log C)`
`= (14)/(2) + (1)/(2)pK_(a) + (1)/(2) log C = 7 + (1)/(2)pK_(a)(CH_(3)COOH) + (1)/(2) + log["Salt"]`