A 11.5 mL aliquot of 0.162 M H₃PO₄ (aq)is to be titrated with 0.229 M NaOH (aq). What volume (mL)of base will it take to reach the equivalence point? A)24.4 B)1.28 C)8.14 D)2.71 E)103

Question

Quizplus · Accepted Answer

The balanced equation for the reaction is H3PO4 + 3NaOH → Na3PO4 + 3H2O. The mole ratio of H3PO4 to NaOH is 1:3. Calculate moles of H3PO4: 0.0115 L * 0.162 mol/L = 0.001863 mol. Moles of NaOH needed = 3 * 0.001863 mol = 0.005589 mol. Volume of NaOH = 0.005589 mol / 0.229 mol/L = 0.0244 L = 24.4 mL.

A 115 ML Aliquot of 0