For a dilute solution having molality `m` of of a given solute in a solvent of mol.wt.`M,b.pt. T_(b)` and heat of vaporisation per mole `DeltaH:[(aT_(b)/(am)]_(mrarr0)` is equal to :

Options

A. Molal elevation constant of solvent
B. `(RT_(b)^(2)M)/(DeltaH_("vap")), where `M` in `kg DeltaH_("vap")` and `R` in `J` mol`^(-1)`
C. `(RT_(b)^(2)M)/(DeltaS_("vap")), where `M` in `kg, DeltaS_("vap")` and `R` in `J` mol`^(-1)`
D. `(RT_(B^(2)M))/(1000DeltaH_("vap"))`, where `M` in `g, R` and `DeltaH_("vap")` expressed in same unit of heat.

Explanation

`DeltaT_(b)=mK_(b)i ,K_(b)=(RT^(2))/(1000DeltaH_("vapour"))`