Here's why:
* Covalent Bonding: Nitrogen and chlorine are both nonmetals. Nonmetals tend to share electrons to achieve a stable electron configuration, forming covalent bonds.
* Electron Sharing: Nitrogen needs three more electrons to complete its outer shell, and chlorine needs one more electron. In NCl3, nitrogen shares one electron with each of the three chlorine atoms, while each chlorine atom shares one electron with the nitrogen atom. This results in a stable configuration for all the atoms.
