Answer: ionic compound
Explanation:
An ionic compound is formed when one element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and forms a positively charged ion called as cation. The element which accepts the electrons is known as electronegative element and forms a negatively charged ion called as anion.
For formation of sodium chloride:
Electronic configuration of sodium:
[tex][Na]=1s^22s^22p^63s^1[/tex]
Sodium atom will loose one electron to gain noble gas configuration and form sodium cation with +1 charge.
[tex][Na^+]=1s^22s^22p^63s^0[/tex]
Electronic configuration of chlorine:
[tex][Cl]=1s^22s^22p^63s^23p^5[/tex]
Chlorine atom will gain one electron to gain noble gas configuration and form chloride ion with -1 charge.
[tex][Cl^-]=1s^22s^22p^63s^23p^6[/tex]
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic compound.