Molarity (M) of an aqueous solution containing x g of anhyd. CuSO4 in 500 mL solution at 32°C is 2×10-1 M. Its molality will be _____ ×10-3m. (nearest integer).
[Given density of the solution = 1.25 g/mL] [2024]
(164)
Wsolution=dsolution×Vsolution=1.25 gmL×500 mL=625 g
nsolute=Molaritysolution×Vsolution=2×10-1 M×0.5 L=0.1 mol
Wsolute=nsolute×molar mass of solute=0.1 mol×159.5 gmol-1=15.95 g
Wsolvent=Wsolution-Wsolute=625 g-15.95 g=609.05 g
m=nsolute×1000Wsolvent (in g)=0.1×1000609.05m=0.1642 m=164×10-3 m