Question

1.8 g of oxalic acid ( H₂C₂O₄) is dissolved in 200 mL of a solution. Find out the molarity of the resultant solution.

Answer 1

Hint: Molarity = number of moles of solute / volume of solution in liter

Step 1: Molar mass of H₂C₂O₄ = 2 + 24 + 64

= 90 g mol^-1

Step 2: No. of moles = given mass/ molar mass

= 1.8 / 90 = 1/50 = 0.02 moles

Volume of solution = 200 mL = 200 / 1000 L = 0.2 L

Molarity = Number of moles of solute / Volume of solution in liter

Molarity = 0.02 / 0.2 = 1 / 10 = 0.1 M

Final Answer : The molarity of the resultant solution is 0.1 M.