Consult the periodic table. an electrically neutral atom has the following electron configuration: 1s2 2s2 2p6 3s2

The element having given electronic configuration is magnesium.

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 electronic configuration.

Atomic number is defined as the number of electrons or number of protons present in a neutral atom.

We are given an electronic configuration:

The total number of electrons = [2 + 2 + 6 + 2] = 12

The atom having atomic number 12 is magnesium.

Hence, the element having given electronic configuration is magnesium.

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