Question

Identify the element with 3 energy levels and 2 valence electrons.

Answer 1

Answer: The element is Magnesium.

Step-by-step explanation:

The energy levels determine the period of the element. Thus an element with 3 energy levels will be an element of third period.

As the valence electrons are 2 , the group number of the element is 2.

Thus the element will have an electroni configuration of
`1s^22s^22p^63s^2`

The atomic number will be equal to the number of electrons and thus atomic number will be (2+2+6+2) = 12. The element will be magnesium with atomic symbol of Mg.