What is the pH of a solution prepared by mixing 50 ml of 0.2 M HCl and 50 ml of 0.1 M NaOH?
- 1.3
- 7.0
- 12.7
- 2.0
📝 Detailed explanation
moles H⁺ = 0.05 * 0.2 = 0.01.moles OH⁻ = 0.05 * 0.1 = 0.005.
Excess H⁺ = 0.01 - 0.005 = 0.005 mol.
Total volume = 0.1 L.
[H⁺] = 0.005 / 0.1 = 0.05 M.
pH = -log(0.05) ≈ 1.3.