Question

Which of the following statement(s) is/are true?

• A. Larger is the magnitude of ionisation enthalpy, easier is the formation of cation
• B. Larger is the magnitude of electron gain enthalpy, easier is the formation of anion
• C. Larger is the magnitude of ionisation energy as well as electron affinity, smaller is the Mulliken electronegativity of atom
• D. Larger is the $Z_{eff}$, larger is the size of atom

Answer 1

The correct option is B Larger is the magnitude of electron gain enthalpy, easier is the formation of anion

(A) Larger the magnitude of ionisation enthalpy, tougher will be the removal of electron to form cation.

(B) Electron gain enthalpy is a measure of the ease with which an atom receives the additional electron in its valence shell in isolated gaseous phase. So, larger is the value of electron gain enthalpy, easier is the formation of anion.

(C) $\text{Electronegativity (Mulliken)}=\frac{\text{Ionisation energy + Electron affinity}}{2}$

(D) As $Z_{eff}$ increases, the valence shell electrons as well as the inner shell electrons are more strongly attracted by the nucleus. This causes the contraction in atomic size.