A solution containing 2.5 g of a non-volatile solute in 100 gm of benzene boiled at a temperature 0.42K higher than at the pure solvent boiled. What is the molecular weight of the solute? The molal elevation constant of benzene is "2.67 K kg mol"^(-1).

A solution containing 2.5 g of a non-volatile solute in 100 gm of benz

1.	A solution containing 2.5 g of a non-volatile solute in 100 gm of benzene boiled at a temperature 0.42K higher than at the pure solvent boiled. What is the molecular weight of the solute? The molal elevation constant of benzene is "2.67 K kg mol"^(-1).
Answer» SOLUTION :`K_(b)="2.67 K KG mol"^(-1)` `DeltaT_(b)=0.42K` `W_(1)=100g=(100)/(1000)kg=0.1Kg` `W_(2)=(K_(b))/(DeltaT_(b)).(W_(2))/(W_(1))` `M_(2)=(2.67)/(0.42)XX(2.5)/(0.1)` `M_(2)="158.98 g mol"^(-1)`