Question

why bond between same type of atom is always non polar bonds ?​

Answer 1

Bonds that are partly ionic are called polar covalent bonds. Nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal. The result is a bond where the electron pair is displaced toward the more electronegative atom.

Answer 2

Answer:

Same types of atom form covalent bonds and hence no charge develops between them like in ionic bonds. And we know that Polar bonds arise due to presence of charges, hence, same types of atom always form non - polar bonds.