Question

how do sodium and chlorine bond to form salt

Answer 1

Sodium and Chlorine react by ionisation.They form Ions.Sodium has one electron in its valency shell.So,Sodium wants to loose that electron to attain stability.Chlorine has 7 valency electrons.So, Chlorine wants one more electron to attain its octet.So, when these two elements are reacted , Sodium atom donates that valency electron to Chlorine.This forms Salt (NaCl) compound with Sodium cation and Chlorine Anion.