Question

A total of three shells with five electrons in its valence shell

Answer 1

Phosphorus is the element

Its valency is 3

Answer 2

(c) Silicon has a total of three shells, with four electrons in its valence shell (2 electrons in K shell, 8 electrons in L shell and 4 electrons in M shell). (d) Boron has a total of two shells, with three electrons in its valence shell (2 electrons in K shell and 3 electrons in L shell).