Question

450 mL of a strong acid solution of pH = 2.0 is mixed with 550 mL of another acid solution of pH = 3.0. The pH of resultant solution is

• A. 2.10
• B. 2.31
• C. 2.55
• D. 2.89

Answer 1

The correct option is B

2.31

[$H+$] from 450 ml pH 2.0 solution = 0.01x(450)/1000
[$H^{+}$] from 550 ml pH 3.0 solution = 0.001x(550)/1000
Adding both [H⁺] = 5.05 x 10^-3

Hence, $pH\approx 2.3$

(log 5 = 0.7)