25 ml of milk were titrated with a 0.124M KOH solution of potassium hydroxide. If 4.5 ml of KOH solution were required to reach the titration endpoint, with a percentage (% w / v) lactic acid present in the milk? (MM = 90.08g / mol)

Answer 1

Lactic acid is a monoprotic acid which I will designate as HL.
HL + KOH ==> KL + H2O
Then mols KOH used = M x L = ?
mols HL = mols KOH since the equation is 1:1 in HL:KOH
grams HL = mols HL x molar mas HL = ?
Then % w/v = (grams HL/25 mL)*100 = ?