The electron configuration of an element is 1522s22p63523p6451. Why is this a REPRESENTATIVE element? A)
All orbitals are completely filled.
B)
The outermost electron is a valence electron.
The outermost electron is added to the p-orbital.
D
The highest s-orbital or p-orbital is partially filled.

See explanation

Explanation:

First of all, we must remember that this compound bears a striking similarity to N2H4 (hydrazine). It must be a chlorine analogue of hydrazine.

Hydrazine is a covalent molecule, hence N2Cl4 must also be a covalent compound. It is formed by the reaction; N2 + 2Cl2 → N2Cl4 and is trivially called tetrachlorohydrazine. Generally, hydrazines contain the N-N  single bond in inorganic compounds.

Systematically, the name is dinitrogen tetrachloride because it contains two nitrogen atoms directly bonded to each other. Each of the nitrogen atoms is bonded to two other chlorine atoms making a total of four chlorine atoms in the molecule.