Answer:
sodium (Name) and Chlorine (Cl)
Explanation:
Any of the Group 17 elements (the halogens) only need one additional electron to take on the electron configuration of the noble gas just to it's right. That would be argon (Ar) in this case.
For this reaction, the needs of both elements (to reach a stable Group 17 electron configuration) is matched: Just one electron is provided (Na) and taken (Cl) and that forms a single bond
