Question

What would be the molarity of one litre solution of 22.2 g of CaCl\(_2\)?

• A. 0.2 M
• B. 0.4 M
• C. 0.6 M
• D. 0.8 M

Hint:

To calculate molarity, divide the moles of solute by the volume of the solution in liters. Ensure the mass and molar mass units are consistent.

Answer 1

The Correct Option is A

The molarity (M) is given by: \[ M = \frac{\text{moles of solute}}{\text{volume of solution in liters}} \] The number of moles of CaCl\(_2\) is calculated as: \[ \text{Moles of CaCl}_2 = \frac{\text{Mass}}{\text{Molar mass}} = \frac{22.2 \, \text{g}}{147 \, \text{g/mol}} = 0.15 \, \text{mol} \] Thus, the molarity is: \[ M = \frac{0.15}{1} = 0.15 \, \text{M} \quad (\text{approx} 0.2 \, \text{M} \text{ for the closest match to the options}). \] Thus, the correct answer is Option (A).