Boiling point of a 2 % aqueous solution of a nonvolatile solute A is equal to the boiling point of 8 % aqueous solution of a non-volatile solute B . The relation between molecular weights of A and B is.

Step-by-step solution

For A : 100 gm solution → 2 gm solute A ∴ Molality = 2 / M A 0 . 098 For B : 100 gm solution → 8 gm solute B ∴ Molality = 8 / M B 0 . 092 ∵   ΔT B A = ΔT B B ∴ Molality of A = Molality of B ∴ 2 0 . 098 M A = 8 0 . 092 M B 2 98 × 92 8 = M A M B 1 4 . 261 = M A M B ∴   M B = 4 . 261 × M A