Question

Determine the molarity of a solution made by dissolving 8.36 g of MgCl2 in water where the final volume of the solution is 500.0 mL.

Answer 1

Answer is: the molarity of the solution is 0.176 M.

m(MgCl₂) = 8.36 g; mass of magnesium chloride.

M(MgCl₂) = 95.21 g/mol; molar mass of magnesium chloride.

n(MgCl₂) = m(MgCl₂) ÷ M(MgCl₂).

n(MgCl₂) = 8.36 g ÷ 95.21 g/mol.

n(MgCl₂) = 0.0878 mol; amount of magnesium chloride.

V = 500 mL ÷ 1000 mL/L.

V = 0.5 L; volume of the solution.

c(MgCl₂) = n(MgCl₂) ÷ V.

c(MgCl₂) = 0.0878 mol ÷ 0.5 L.

c(MgCl₂) = 0.176 mol/L; the molarity of the solution.