The electron affinity of Li is `-59.6kJmol^(-1)` which suggests that formation of gaseous `Li^(-)` anion is favourable energetically . If ionization energies of Li,Na and K are 520, 496 and 419 `kJ mol^(-1)`, which of the following compounds has the stability?

Options

A. `Na^(+)Li^(-)`
B. `K^(+)Li^(-)`
C. `Rb^(+)Li^(-)`
D. None of these

Answer

D

Explanation

The energy released in the gain of electron by Li(g) is not sufficient to ionize Na(g),K(g) or Rb(g). The formation of such compounds is not favourable energetically (being endothermic).