Question

The ionic bonds $X^{+}{Y}^{-}$ are formed when:

• A. Electron affinity of $Y$ is low and ionisation energy of $X$ is high
• B. Electron affinity of $Y$ is high and ionisation energy of $X$ is low
• C. Lattice energy of $XY$ is low
• D. None of these

Answer 1

The correct option is B Electron affinity of $Y$ is high and ionisation energy of $X$ is low

Ionic bonds are only possible when $X$ can easily lose electrons and Y can accept electrons easily i.e, ionisation energy of $X$ should be low and electron gain enthalpy of $Y$ should be high.