On dissolving 2.34g of non-electrolyte solute in 40g of benzene, the boiling point of solution was higher than benzene by 0.81K. Kb value for benzene is 2.53 K `kgmol^(-1)` .Calculate the molar mass of solute. [Molar mass of benzene is 78 `gmol^(-1)`]

Explanation

`M_2 = (K_b + w_2xx 1000)/( DeltaT_b xx w_1)`
`K_b = 2.53 K "mol"^(-1) " " w_1 = 40g , w_2 = 2.34 g `,
` M_2 = ? , DeltaT_b = 0.81 K `
` M_2 = (2.53 xx 2.34 xx 1000)/(0.81 xx 40)`
`= 182. 7 g mol^(-1)`