If aqueous solution contains 9% and 1% `(W//W)` of two non- volatile non- electrolytes X (molecular weight 180) and Y (mulecular weight 50 ) respectively the boiling point of solution in`.^(@)C` approximately is
`(k_(b) = 0.52 kg mol^(-1))`

Options

A. 101.4
B. 100,4
C. 102.4
D. 100.8

Answer

B

Explanation

Mass of non- volatile solute x= 9 g
Mass of non- volatile solute Y = 1 g
Molar mass of Y = 50 g `mol^(-1)`
Mass of solvent = (approx ) =100
`Delta T_(b) = K_(b) xx M = K _(b) [M_((x)) + M_((Y)) ]`
` = k_(b) [(w_((x)))/(M_((x))) + (W_((y)))/(M_((y))) ] xx (1000)/(100)`
`0.52 [0.05 + 0.02] 10`
Thus boiling point = 100 + 0.36
`100.36 ` or 100.4
Hence option (b ) is the correct answer