Question

How many electrons are there in the valence quantum level of copper (At No.29). Give reasons.

Answer 1

9 electrons from the d shell are in the 3d shell (the numbers of d shift up 1 from their position on the periodic table). it only has 2 valence electrons in the 4s shell..

Answer 2

Answer: Copper has 1 electron in its valence shell.

Explanation:

Valence electrons are defined as the electrons that are present in the outermost shell of an atom. The shell having highest value of principal quantum number is known as valence shell.

Copper is the 29th element of the periodic table having electronic configuration of $[Ar]3d^{10}4s^1$

The valence shell of this element is 4s. This shell has only 1 electron.

Hence, copper has 1 electron in its valence shell.