Question

The end point in a titration of a 43ml sample of aqueous lactic acid was reached by addition of 16mlof0.22MKOH titrant. One mole of acid was titrated by one mole of base. What is the molar concentration of lactic acid

Answer 1

Answer:

0.082 M

Explanation:

First we calculate the moles of KOH added, by multiplying its volume and concentration:

• 0.22 M * 16 mL = 3.52 mmol KOH

Given that one mole of acid reacts with one mole of base, in the lactic acid sample there were 3.52 acid moles as well.

Finally we divide the acid moles by the volume, to calculate the concentration:

• 3.52 acid moles / 43 mL = 0.082 M