Determining the volume of base needed to titrate

Question

A chemistry student weighs out 0.106 g of ascorbic acid H2C6H6O6, a diprotic acid, into 250. mL volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.0700 M NaOH solution. Calculate the volume of NaOH solution the student will need to add to reach the final equivalence point round tour answer to 3 sig figs

Answer 1

Assuming the titration will take place on the entire 250 ml sample of ascorbic acid, and not on a sample of it, we can proceed as follows:

mols ascorbic acid (AA) = 0.106 g x 1 mol ascorbic acid / 176.1 g = 0.0006019 mols

H₂C₆H₆O₆ + 2NaOH ==> 2H₂O + Na₂C₆H₆O₆ ... balanced equation for titration

mols NaOH needed = 0.0006019 mols AA x 2 mol NaOH / mol AA = 0.001204 mols NaOH needed

volume of 0.0700 M NaOH = 0.001204 mols NaOH x 1 L / 0.0700 mols = 0.0172 L NaOH = 17.2 mls NaOH