Lowering of vapour pressure of an aqueous solution of a non-volatile non-electrolyte 1 m aqueous solution at 100°C is,

Question

Lowering of vapour pressure of an aqueous solution of a non-volatile non-electrolyte 1 m aqueous solution at 100°C is, (A) 14.12 Torr (B) 312 Torr (C) 13.45 Torr (D) 352 Torr

Tardigrade Admin · Accepted Answer

p° = 760 Torr A 1 m aqueous solution contains 1 mol of solute in 100 g (55.5 mol) of water ∴ xB = (1/ 1+ 55.5) = (1/56.5) (Δp/p) = xB Δ p = pxB = (760 Torr/56.5) = 13.45 Torr.

Q. Lowering of vapour pressure of an aqueous solution of a non-volatile non-electrolyte 1 m aqueous solution at 100 $^{\circ}$ C is,

14.12 Torr

312 Torr

13.45 Torr

352 Torr

$p^{\circ}$ = 760 Torr
A 1 m aqueous solution contains 1 mol of solute in 100 g (55.5 mol) of water
$∴$ $x_{B} = \frac{1}{1 + 55.5} = \frac{1}{56.5}$
$\frac{Δ _{p}}{p} = x_{B}$
$Δ p = p x_{B} = \frac{760 T orr}{56.5}$ = 13.45 Torr.

Q. Lowering of vapour pressure of an aqueous solution of a non-volatile non-electrolyte 1 m aqueous solution at 100∘C is,