Question

Helium has two electrons in its valence shell but its valency is not two.explain why? In 2-3 lines

Answer 1

This element is already stable.
Because there are 2 electron in valence shell.
As we know that if there are 8 or 2 electron present in valence shell then the element is already stabled.Due to this the element has no need to make it's valency.

Answer 2

Hydrogen and helium work a little differently because their valence shell (the first shell) can only hold 2 electrons. This means that helium is chemically stable with a valency of 0 since its valence shell is full. Hydrogen, with only 1 electroncould either gain or lose an electron to become stable.