Question

the element x has 1 electron in the s subshell in 3rd shell
a)write the compleate electronic configuration of x
b)find out the atomic number of this element
c) if x combains with another element y of valncy 2,write the chemical formula of compund formed

Answer 1

Answer:

The E.C would be 1s2 2s2 2p6 3s1

atomic no. : 2 + 2 + 6 + 1  11

It is Na

Explanation:

Answer 2

The element is Na.

• The element x has 1 electron in the s subshell in the 3rd shell thus it has one electron in the 3s shell.
• a) The electronic configuration of the element is-
• ${1s}^{2} {2s}^{2} {2p}^{6} {3s}^{1}$
• b) The atomic number of the element is 11.
• c) Thus x has valency 1 and y has vacancy 2 so, the formula of the formed compound will be given as $x_2y$.