Potassium hydrogen phthalate is used as a primary standard in finding the concentration of a solution of sodium hydroxide by the reaction KHC₈H₄O₄ + NaOH $\rightarrow$NaKC₈H₄O₄ + H₂O.What is the molarity of the base if 32.75 mL is required to titrate 1.732 g of the primary standard?

Question

Quizplus · Accepted Answer

The molar mass of potassium hydrogen phthalate (KHC8H4O4) is approximately 204.22 g/mol. The moles of KHC8H4O4 are 1.732 g / 204.22 g/mol = 0.00848 mol. Since the reaction is 1:1, moles of NaOH = moles of KHC8H4O4 = 0.00848 mol. Molarity (M) = moles/volume (L) = 0.00848 mol / 0.03275 L = 0.2590 M.

Potassium Hydrogen Phthalate Is Used as a Primary Standard in Finding