Question

An element has 2 electrons in its N shell,

(iii) is it metal or nonmetal?

Answer 1

The configuration of elements having 2 electrons in their N shell can be written as shown below.

Shells	K	L	M	N
Electrons present in each shell	2	8	8	2

• The electronic configuration (2 8, 8, 2) defines that the element has the atomic number 20.
• Since the element has 2 electrons in its valence shell, it has a tendency to readily lose its valence electrons to gain stability thus, it is a metal.

Hence, the element with atomic number 20 is calcium which is a metal.