Electronic configuration of some elements is given in Column I and their electron gain enthalpies are given in Column II. Match the electronic configuration with electron gain enthalpy.

Column I

(Electron configuration)

Column II

(Electron gain enthalpy/kJ mol–1)

A. 

1s22s22p6

1.

–53

B. 

1s22s22p63s1

2.

–328

C. 

1s22s22p5

3.

–141

D. 

1s22s22p4

4.

+48

Codes:

Options:  A   B   C   D 
1.  4 1 2 3
2. 1 2 3 5
3. 1 4 3 2
4. 4 1 3 2

 
A.(4) B.(1) C.(2) D.(3)
A. This electronic configuration corresponds to the noble gas i.e., neon. Since, noble gases have +egH values, therefore, electronic configuration (A) corresponds to the egH=+48 kJ mol-1.
B. This electronic configuration corresponds to the alkali metal i.e., potassium. Alkali metals have small negative egH values, hence, electronic configuration (B) correspongds to egH=-53 kJ mol-1.
C. This electronic configuration corresponds to the halogen i.e., fluorine. Since, halogens have high negative egH values, therefore, electronic configuration (C) corresponds to egH=328 kJ mol-1.
D. This electronic configuration corresponds to the chalcogen i.e., oxygen. Since, chalcogens have egH values less negative than those of halogens, therefore, electronic configuration (D) corresponds to egH=-141 kJ mol-1.