Calculate the volume of a 36% solution of hydrochloric acid (density = 1.50g/mL, molar mass = 36 g/mol) required to prepare 9 liters of a 5 molar solution.

A. 1 liter
B. 2 liters
C. 3 liters
D. 4 liters
E. 5 liters

1 answer

To prepare 9 litres of 5 molar we need

45 moles of HCl

which is 36x45 g = 1620 g of HCl

if the stock solution is 36w/w% then we need

1620 g/0.36 of the stock = 4500 g of the stock.

to find the volume needed
volume = mass/density

volume = 4500 g/1.50 g/ml
=3000 ml