The lattice energy of solid `NACl` is `180K. Cal mol^(-1)`. The dissolution of the solid in water in the form of ions is endothermic to the extent of `1 K.cal mol^(-1)`. If the hydration energies of `NA^(+)` and `Cl^(-)` are in ratio `6 : 5`, what is the enthalpy of hydration of `NA^(+)` ion

Options

A. `-85.6 K. cal mol^(-1)`
B. `-97.5 K.cal mol^(-1)`
C. `-182.6 K.cal mol^(-1)`
D. `+100K. Cal mol^(-1)`

Answer

B

Explanation

`DeltaH_(sol^(n))=DeltaH_(L.E)+DeltaH_(H.E)`