Calculate the molarity of the two solutions.

Question

The first solution contains 0.400 mol of NaOH in 2.35 L of solution.

molarity =

The second solution contains 17.7g of NaCl in 695mL of solution.

molarity=

Answer 1

Definition of molarity is moles of solute per liter of solution

First problem: 0.400 moles / 2.35 L solution = 0.170 M (3 sig. figs.)

Second problem: 17.7 g NaCl x 1 mol NaCl / 58.44 g = 0.3029 moles

695 ml x 1 L/1000 ml = 0.695 L

molarity = 0.3029 moles/0.695 L = 0.436 M (3 sig. figs.)