Question

An aqueous solution of cesium chloride is prepared by dissolving 52.3 g cesium chloride in 60.0g of water at 25°C. The volume of this solution is 63.3 mL . What is the molarity of the solution?

Answer 1

Given data:

Mass of cesium chloride CsCl (m) = 52.3 g

Mass of water (mh2O)= 60.0 g

Volume of the solution (V) = 63.3 ml

Step 1: Calculate the number of moles of CsCl

Molar mass of CsCl = 168.36 g/mol

Mass of CsCl = 52.3 g

# moles = mass/molar mass = 52.3 g/168.36 g.mol-1 = 0.3106 moles

Step 2: Volume of solution in Liters

1000 ml = 1 liter

therefore, 63.3 ml corresponds to : 63.3 ml * 1 L/1000 ml = 0.0633 L

Step 3: Calculate molarity of CsCl

Molarity = moles of CsCl/volume of solution

            = 0.3106 moles/0.0633 L = 4.91 moles/L

Molarity = 4.91 M