Question

a sollution is prepared by dissolving 30 g of urea in 120 g of water calculate the mass by mass percentage of urea in solution

Answer 1

Answer:

Molarity = Number of moles of solute/Volume of solution in Litres

Moles of urea = Given mass/Molecular mass = 12060 = 2 mol

Volume of solution = Mass of solution/Density of solution= (120+1000) g/1.15 g.mL−1= 974 ml or 0.974 L

Hence, Molarity = 2 mol/0.974 L = 2.05 mol L−1