* Electronegativity: Chlorine is more electronegative than sodium. Electronegativity is the ability of an atom to attract electrons towards itself in a chemical bond. Chlorine has a higher electronegativity than sodium, meaning it has a stronger pull on electrons.
* Octet Rule: Both sodium and chlorine want to achieve a stable electron configuration like that of a noble gas. Sodium has one valence electron in its outermost shell, while chlorine has seven. By gaining one electron, chlorine completes its octet (eight electrons in its outermost shell), making it stable.
* Ionic Bond Formation: When sodium and chlorine react, sodium readily loses its one valence electron to become a positively charged ion (Na+). This electron is then gained by chlorine, making it a negatively charged ion (Cl-). The opposite charges between Na+ and Cl- then attract each other, forming an ionic bond and creating the compound NaCl.
In summary: Chlorine gains an electron in NaCl because it's more electronegative and by doing so, it achieves a stable electron configuration, fulfilling the octet rule. This electron transfer forms an ionic bond between the positively charged sodium ion and the negatively charged chloride ion.
