Question

What is the molarity of a saline solution that contains 105 g of NaCl at a volume of 250mL

Answer 1

Molarity means the number of moles of solute per litre of solution.

The unit is mol L⁻¹

Molarity = moles of solute (mol) / volume of solution (L)

Moles of NaCl = 105 g / 58.5 g mol⁻¹

=1.79 mol

Molarity = 1.79 mol / 0.250 L

Molarity = 7.16 mol L⁻¹