defence exam BSF Head Constable (RO/RM) Mock Test 2023 General Science Chemistry Classification of Elements and Periodicity in Properties
The electronic configuration of the most electronegative element is:
1
1s2 2s2 2p4
2
1s2 2s2 2p6 3s2 3s5
3
1s2 2s2 2p5
4
1s2 2s2 2p6