Question

The mass of a non-volatile solute (molar mass 80 g mol^-1) which should be dissolved in 92 g of toluene to reduce its vapour pressure to 90% ……….. 

(a) 10 g 

(b) 20 g 

(c) 9.2 g 

(d) 8.89 g

Answer 1

(d) 8.89 g

W₂ = 80 / 9 

= 8.89 g