Word-Definition
Pure substance- 4
Matter- 2
Atom- 1
Molecule- 3
Element- 5
The middle nitrogen has two sigma bonds and one pi bond. You know that one p orbital is used in the double bond and two sp2 orbitals are involved in the sigma bond. This leaves one sp2 orbital for the lone pair to occupy.
Maximum number of electrons in nth energy level

Now
Max electrons


Answer:
In explanation.
Explanation:
In the file attached is the answer, couldn´t answer it here.