Question

Potassium hydrogen phthalate (molar mass = 204.2 g/mol) is one of the most commonly used acids for standardizing solutions containing bases. KHP is a monoprotic weak acid with Calculate the pH of the solution that results when 0.40 g of KHP is dissolved in enough water to produce 25.0 mL of solution.

Answer 1

pH = 1.1

Step-by-step explanation:

number of moles of KHP = 0.4/204.2 = 0.002

KHP ⇒ k⁺ + HP⁻

HP⁻ + H₂O ⇒ P⁻ + H₃O⁺

1 mole of KHP disolves in water and produces 1 mole of H₃o⁺

so 0.002 of KHP produce 0.002 mole of H₃O⁺

the concentration of H₃O⁺ = 0.002/(25/1000) = 0.08

pH = -log(0.08) = 1.1