Question

50mL of 2N acetic acid mixed with 10mL of 1N sodium acetate solution will have an approximate pH:

• A. 7
• B. 6
• C. 5
• D. 4

Answer 1

The correct option is D 4

Mixture of $2N$ acetic acid and $1N$ sodium acetate will act as buffer.

$\therefore pH=p{K}_a+\log \frac{\left[sodiumacetate\right]}{\left[aceticacid\right]}$

$=4.74+\log \frac{\left(\frac{10\times 1}{10+50}\right)}{\left(\frac{50\times 2}{10+50}\right)}=4.74-1=3.74\approx 4$ .