Chemistry/ Concentration

Question

A sample of Potassium hydrogen oxalate, KHC2O4, with a mass of 0.832 grams was dissolved in water and titrated with 25.80 mL of a sodium hydroxide solution. Calculate the molarity of the sodium hydroxide solution.

Answer 1

First we must determine the the moles of KHC₂O₄ in the solution.

0.832 g KHC₂O₄ ÷ 128.125 g mol^-1 = 0.00649 mol KHC₂O₄

We know every mole of KHC₂O₄ is titrated with one mole of NaOH, therefore we now know 0.00649 mol of NaOH were used to titrate the KHC₂O₄.

0.00649 mol NaOH ÷ 0.2580 L = 0.0252 M NaOH or 25.2 mM NaOH