Solutions — Medium JEE chemistry MCQ
**[JEE Mains 2026]** 100 g of 98% (by weight) H₂SO₄ is mixed with 100 g of 49% (by weight) H₂SO₄. What is the mole fraction of H₂SO₄ in the resulting solution?
- A. 0.25
- B. 0.35
- C. 0.18
- D. 0.28
Solution
Mass of H₂SO₄ from 98% solution = 98 g, moles = 98/98 = 1 mol.
Mass of H₂SO₄ from 49% solution = 49 g, moles = 49/98 = 0.5 mol.
Total H₂SO₄ moles = 1.5 mol.
Mass of water = (100-98) + (100-49) = 2 + 51 = 53 g, moles = 53/18 ≈ 2.94 mol.
Mole fraction of H₂SO₄ = 1.5/(1.5 + 2.94) = 1.5/4.44 ≈ 0.28.