0.02M solution of sucrose is isotonic with 0.008M solution of sodium sulphate. What is the percentage dissociation of the electrolyte?

Step-by-step solution

For isotonic solutions, the osmotic pressures are equal. _ sucrose = _ Na₂SO₄ i₁ C₁ RT = i₂ C₂ RT For sucrose (a non-electrolyte), i₁ = 1 . 1 0.02 = i₂ 0.008 i₂ = 0.02 0.008 = 2.5 Sodium sulphate ( Na₂SO₄ ) dissociates into 3 ions ( 2Na^+ and SO₄²⁻ ), so n = 3 . The van't Hoff factor is given by i = 1 + (n - 1) . 2.5 = 1 + (3 - 1) 2.5 = 1 + 2 2 = 1.5 = 0.75 Percentage dissociation = 0.75 100 = 75 % . Answer: 75