Question

Helium atom has two electrons in its valence shell but its valence is not two?
pls do it fast...

Answer 1

Solution:

⇒ Helium atom has 2 electrons in its valence shell and its valence is not two because its duplet is complete. Hence, the valency is zero.

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Answer 2

The atomic number of Helium is 2

So the Electronic Configuration of Helium is

K     L

1      1

Valence Electrons are those electrons which are in the last shell.

In this case the valence electron is 1

Valency is the number of Electrons an atom requires in its last shell to become stable.

In this case of Helium the electron required in last shell is 1 because in the L shell the maximum number of electrons which can accommodate is only 1.

And that's why the valency of Helium is 1

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