Which part of the atom is involved in chemical bonding with other atoms?

Concept:

When an atom has incomplete number of electron in its outermost orbit then it has great tendency to react with another atom which satisfies their octate either by sharing or by transferring their electrons. The involved electrons are called valence electrons.

In case of electrovalent compound, the valance electron complete their octate by transferring their valence electrons while in the covalent compound, they complete their octate by the sharing of their valence electrons.

Hence, the valence electron of the atom is involved in chemical bonding with other atoms.

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.