Question

An ionic compound $A^{+}{B}^{-}$ is most likely to be formed when:

• A. The ionization energy of $A$ is high and the electron affinity of $B$ is low
• B. The ionization energy of $A$ is low and the electron affinity of $B$ is high
• C. Both the ionization energy of $A$ and the electron affinity of $B$, are high
• D. Both the ionization energy of $A$ and electron affinity of $B$, are low

Answer 1

The correct option is B The ionization energy of $A$ is low and the electron affinity of $B$ is high

The formation of an ionic compound will depend upon:
1. Ionization energy
2. Electron affinity
Ionization energy is the energy required to remove an electron from a neutral gaseous atom. Lower the ionization energy, greater is the ease of formation of a cation.
Electron affinity is the energy released when an electron is added to a neutral atom to form a negative ion. Higher the electron affinity, greater is the ease of formation of an anion.
Therefore, option (b) is correct.