Question

13. Subshell electronic configuration of some elements are given.
(Symbols are not real)
A - 1s 2s 2p 3s 3p
B - 1s 2s 2p 3s 3p
C-Is? 2s 2p 3s 3p 3d 4s?
D - 1s 2s 2p 3s 3p 4s?
a) Which element among these shows -2 oxidation state?
b) Which element has the highest metallic character?
c) Which element has the highest ionisation energy?
d) Write the chemical formula of the compound formed by the
elements A and D.​

Answer 1

Explanation:

(a) The correct electronic configuration of element A is:

1s22s22p63s23p64s1

(b) Fourth period.

(c) The electronic configuration of element A is

1s22s22p63s23p64s1

The electronic configuration of element C is

1s22s22p63s1

From the electronic configuration of the elements A and C, the atomic size of A is greater than the atomic size of C. Hence, the distance between the outermost electron of element A and its nucleus is more than the distance between the outermost electron and nucleus of element C. As the atomic size increases, the effective nuclear attraction experienced by the outermost electron decreases. Therefore, among the atoms A and C, the attraction of the nucleus towards the outermost electron is greater in case of element C.