Given:
KOH used to make 1.6 liters of 15% by mass solution with water
Required:
grams of KOH
solution:
the density of KOH is equal to 2.12 kg/L
multiply the known volume of KOH to the density and the percentage of KOH in water
mass of KOH = 1.6 L (2.12 kg/L)(0.15) = 22.61 grams of KOH