Question

The element that has a valence configuration of 2s2 is ________.

Answer 1

Answer: The element having given valence electronic configuration is beryllium.

Explanation:

Electronic configuration is defined as the representation of electrons around the nucleus of an atom. Number of electrons in an atom are determined by the atomic number of that atom.

Valence electrons are defined as the electrons present in the outermost shell of an atom.

We are given:

Valence electronic configuration of an atom = $2s^2$

So, the actual electronic configuration of atom will be $1s^22s^2$

Total number of electrons = 2 + 2 = 4

So, the atomic number of given element is 4 and the element is beryllium

Hence, the element having given valence electronic configuration is beryllium.

Answer 2

Be 1s²2s²,  [He]2s²
beryllium  (2- second period, s² - 2A group)