Question

Calculate the pH of a solution that is 0.291 M acetic acid and 0.123 M sodium acetate. The Ka of acetic acid is 1.76×10^–5 at 25°C. What is the pH of this mixture at 0°C?

Answer 1

The answer is "4.37."

Step-by-step explanation:

at
`0^(\circ) C\ Ka = 1.76 * 10^(-5)`

`\to pKa = - \log \ Ka`

`= - \log \ 1.76 * 10^(-5)\\\\ = 4.75`

`pH = pKa + \log ([sodium \ acetate])/([acetic \ acid])`

`= 4.75 + \log ([0.123])/([0.291])\\\\= 4.75+ \lg(0.422680412)\\\\=4.75-0.373987878\\\\=4.37601212\\\\=4.37`