Question

A solution of sodium hydroxide is standardized against potassium hydrogen phthalate. From the following data, calculate the molarity of NaOH solution. Mass of KHP used: 0.4536 g Buret reading before titration: 0.23 ml Buret reading at the end point: 31.26 ml

Answer 1

0.7158 Mol/L

Step-by-step explanation:

KHC8H4O4 + NaOH → H2O + KNaC8H4O4

KHC8H4O4 molar mass = 204.2212 g/mol

0.4536 g of KHC8H4O4 = 2.221 mMol (10^-3 mol)

volume = 31.26 mL - 0.23 mL = 31.03 mL

NaOH concentration = 2.221 mMol/31.03 mL = 2.221 Mol/31.03 L = 0.7158 Mol/L