JEE Main 2024 Chemistry question
The molarity of 1 L orthophosphoric acid (H₃PO₄) having 70% purity by weight (specific gravity 1.54 g cm⁻³) is M. (Molar mass of H₃PO₄ = 98 g mol⁻¹)
Answer: 11
Solution
Mass of the solution = 1540 g. Mass of H₃PO₄ = 1540 × 0.70 = 1078 g, which is 1078/98 = 11 mol in 1 L. So the molarity is 11 M.