Answer:
[H⁺] = 0.00175 M
pH = 2.757
Step-by-step explanation:
The ionization of benzoic acid is given below:
C₆H₅COOH ----> C₆H₅COO⁻(aq) + H⁺(aq)
1 mole of H⁺ ions are produced from the dissociation of 1 mole C₆H₅COOH.
Therefore 0.050 M benzoic acid produces 0.050 M H⁺.
However, the benzoic acid is only 3.5% ionized, therefore concentration of H+ ion, [H⁺] = 3.5/100 * 0.050 M
[H⁺] = 0.00175 M
pH = - log[H⁺]
pH = - log(0.00175)
pH = 2.757