Question

The pKa of acetic acid and pKb of ammonium hydroxide or 4.76 and a 4.75 respectively calculate the pH of ammonium acetate solution.

Answer 1

we know, acetic acid is acid and ammonium hydroxide is base. reaction between acetic acid and ammonium hydroxide is ....
$CH_3COOH+NH_4OH\rightarrow CH_3COONH_4+H_2O$

use formula,

$\quad\bf{pH=7+\frac{1}{2}[pK_a-pK_b]}$

here it is given that,

pKa of acetic acid = 4.76

pKb of ammonium hydroxide = 4.75

so, pH of ammonium acetate = 7 + 1/2 [4.76 - 4.75 ]

= 7 + 1/2 × 0.1

= 7.005

Answer 2

Answer: The pH of the solution comes out to be 7.005

Explanation:

The equation for the reaction of acetic acid and ammonium hydroxide is given as:

$CH_3COOH+NH_4OH\rightarrow CH_3CHOONH_4+H_2O$

The ammonium acetate salt produced is the salt of weak acid and weak base.

To calculate the pH of the solution, we use the equation:

$pH=\frac{1}{2}(pk_w+pk_a-pk_b)$

We are given:

$pk_w=14\\pk_a=4.76\\pk_b=4.75$

Putting values in above equation, we get:

$pH=\frac{1}{2}(14+4.76-4.75)\\\\pH=7.005$

Hence, pH of the solution comes out to be 7.005