100 ml larutan h2so4 0.004 M di campurkan dengan 100 ml larutan hcl 0.02 M, maka pH campuran

n H₂SO₄ = 0,004 M × 100 mL = 0,4 mmol
n HCl = 0,02 M × 100 mL = 2 mmol
v total = 100 mL + 100 mL = 200 mL

H₂SO₄ + 2 H₂O → 2 H₃O⁺ + SO₄²⁻
n H⁺ = n H₃O⁺ = 2 × n H₂SO₄ = 2 × 0,4 mmol = 0,8 mmol
[H⁺] = [tex] \frac{0,8 mmol}{200 mL} [/tex]
[H⁺] = 0,004 M

HCl + H₂O → H₃O⁺ + Cl⁻
n H⁺ = n H₃O⁺ = HCl = 2 mmol
[H⁺] = [tex] \frac{2 mmol}{200 mL} [/tex]
[H⁺] = 0,01M

[H⁺] = 0,004 M + 0,01 M
[H⁺] = 0,014 M

pH = -log [H⁺]
pH = -log 0,014
pH = 1,86