Phenypropanoic acid (C₉H₁₀O₂) is a white, crystalline solid with a sweet floral smell widely used in cosmetics and food flavorings. It is a weak monoprotic base with K_a value of 2.2×10^–5. If 750 mg of C₉H₁₀O₂ is dissolved in 500.0 mL of water, calculate the pH of the solution and the percent ionization.