Question

A 2.30 M aqueous solution of LiCI has a density of 1.0516 g/mL. If the total mass of the solution is 62.0 g, what masses of solute and solvent are present? Mass of LiCl Mass of water

Answer 1

Total volume of the solution,V= mass/ density

V= 62.0 g/1.0516(g/mL)

=59.96 mL

We know that molarity,M= number of moles/ volume in L

So number of moles,N= molarity x volume in L

N = 2.30 M x 58.96 mL x10^-3 L/mL

= 0.136 mol

So mass of LiCl,m= number of moles x molar mass

m= 0.136 mol x 42.4 (g/mol)

= 5.7 g

Therefore the mass of solute,LiCl is 5.7 g

Mass of water = mass of solution - mass of LiCl

= 62.0 - 5.7

= 56.3 g