The answers to the questions are as follows;
Question 1:
Since Nitrogen has 5 Valence electrons, it needs 3 electrons to attain it's octet configuration. As such, it gains 3 electrons.
Question 2:
The quantity which determines how two atoms bond is The difference in their electronegativities.
Question 3:
This is because the elements have filled Valence levels.
Question 4:
The ion which has a stable Valence electron configuration is potassium (K) with a 1+ charge
Question 5;
The chemical formula which represents a polyatomic ion is; ClO-