Question

The molarity of an aqueous solution of glycol is 10 M. The density of the solution is 1.16 g/mL. Find the mole fraction of glycol.

• A. 0.5
• B. 0.25
• C. 0.75
• D. 0.9

Answer 1

The correct option is B 0.25

Given:
Molarity of the solution = 10 M

Assuming 1 litre of the solution,
Moles of glycol = 10 mol
Molar mass of glycol = 62 g/mol
Mass of glycol = 620 g
Volume of the solution = 1 L
Density of the solution = 1.16 g/mL
Mass of the solution = 1160 g
Mass of water = 540 g
Moles of water = 30 mol
Total moles of glycol and water = 40 mol
Mole fraction = $\frac{10}{40}=0.25$