The pH of 0.05 M acetic acid is (K_a=2 10⁻⁵ )

Step-by-step solution

aligned & CH ₃ COOH H ⁺+ CH ₃ COO ⁻ & K_a= [ H ⁺ ] [ CH ₃ COO ⁻ ] [ CH ₃ COOH ] = [ H ⁺ ]^2 [ CH ₃ COOH ] & [ H ⁺ ] = K_a [ CH ₃ COOH ] &= 2 10⁻⁵ 0.05 &= 10⁻⁶ aligned aligned [ H ⁺ ] & =10⁻³ pH & =- [ H ⁺ ] & =- [10⁻³ ] pH & =3 aligned