What is the pH of the resulting solution when equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed?
- 2.0
- 7.0
- 1.04
- 12.65
Answer
(4) 12.65
Solution
Let the volume of each solution be V L.
Moles of OH- = 0.1V; moles of H+ = 0.01V
⇒ OH- left after neutralisation = 0.1V - 0.01V = 0.09V
Total volume = 2V
⇒ [OH-] = 0.09V2V = 0.045 M
⇒ pOH = - (0.045) = 1.35
∴ pH = 14 - 1.35 = 12.65
Answer: (4)