The boiling point of benzene is 353.23 K when 1.80 g of a non-volatile, non-ionising solute was dissolved in 90 g of benzene, the boiling point is raised to 354.11 K. Calculate the molar mass of solute.
`" "`[Given `K_(b)` for benzene = 2.53 K kg `mol^(-1)`]

Explanation

Given `T^(0)=353.23K, T_(b)=354.11K, W_(H)=1.80g,`
`W_(A)=90g, K_(b)=2.53 K" "kg" "mol^(-1)`
`DeltaT_(b)=T_(b)-T_(b)""^(@)`
`" "=354.11-353.23=0.88K`
`M_(B)=(1000 times K_(b) times W_(B))/(DeltaT_(b) times W_(A))=(1000 times 2.53 times 1.8)/(0.88 times 90)=57.5 g`