Question

What is the identity of a 2nd-row element that has three valence electrons?

Answer 1

`"Boron........."`

Explanation:

Boron, `Z=5`, has 3 valence electrons: `2s^(2)2p^1`. Carbon, `Z=6`, has 4 valence electrons: `2s^(2)2p^2`. Nitrogen, `Z=7`, has 5 valence electrons: `2s^(2)2p^3`. And fluorine, `Z=7`, has 7 valence electrons: `2s^(2)2p^5`. Of course, these valence electrons are active in the geometry and structure of the compounds of these species.