Here's why:

* Covalent bonds occur when atoms share electrons to achieve a stable electron configuration.

* Chlorine is a highly electronegative element, meaning it has a strong pull on electrons.

* Carbon also needs electrons to achieve stability.

In a compound like carbon tetrachloride (CCl4), carbon shares its four outer electrons with four chlorine atoms. Each chlorine atom contributes one electron to the shared pair, resulting in four strong covalent bonds between carbon and chlorine.