Q12 / 97 · NTA Abhyas (JEE Main) 2020 · Chemistry · Solutions

At 48°C the vapour pressure of pure C S 2 is 850 torr. A solution of 2.0  g of sulphur in 100 g of C S 2 has a vapour pressure 844.9 torr. Determine the atomicity of sulphur molecule :

  • A
    1
  • B
    2
  • C
    4
  • Correct answer
    D
    8

Solution

Δ P = 5.1 torr ; x is atomicity of sulphur.

Δ P P A ∘ = 5.1 850 = X B = 2 3 2 x 2 3 2 x + 1 0 0 7 6

5.1 850 ≅ 2 3 2 x × 7 6 1 0 0

x = 2 × 7 6 3 2 × 1 0 0 × 8 5 0 5.1 = 7.92 ≈ 8

Hence, the correct answer is option: 'D'.

More Solutions Questions