Given below are two statements :
Statement I : H₂O molecules move from the chamber 1 to chamber 2 .
Statement II : The osmotic pressure of a solution prepared by dissolving 50 mg of potassium sulphate (molar mass =174 g/mol ) in 2 L of water (at 27°C ) is 0.0107 bar. (Given: R=0.083dm³ bar K⁻¹ mol⁻¹ and assume complete dissociation of electrolyte)
In the light of the above statements, choose the correct answer from the options given below :

Solution

Chemistry ma’am · 4 steps

Water follows molarity, not the mass of sugar, and K₂SO₄ gives three ions, so i = 3.

1. Compare the chambers. Glucose has M = 180 g mol⁻¹. Chamber 1 has 18/180 = 0.1 mol in 0.1 L, which is 1 M. Chamber 2 has 30/180 = 0.167 mol in 0.25 L, which is 0.67 M.
2. Direction of osmosis. Water moves through the membrane from the dilute side to the concentrated side. Chamber 2 is more dilute, so water flows from chamber 2 to chamber 1. Statement I is false.

   π = iCRT, K₂SO₄ → 2K⁺ + SO₄²⁻ ⇒ i = 3

3. Put in numbers. Moles of K₂SO₄ = 0.05/174 = 2.87 × 10⁻⁴ mol, so C = 1.44 × 10⁻⁴ mol L⁻¹ in 2 L. Then π = 3 × 1.44 × 10⁻⁴ × 0.083 × 300 = 0.0107 bar. Statement II is true.
4. So. Statement I is false and Statement II is true, which is option (d).

The idea to keep. Solvent always flows toward the higher concentration, so compare molarities and not grams. For electrolytes, multiply by the van't Hoff factor before you use π = iCRT.

Answer from the NTA final answer key. Solution by PrepWiser.