Question

determine whether each reactant gains or loses electrons to form an ionic compound.
4 Na(s)+ O2(g)>2NaO(s)

Answer 1

That chemical bond which involves the complete transfer of electrons is called Ionic bond.

During ionic bond formation one atom loses an electron while the other atoms gains the electrons.

The atom which loses electrons from a a positively charged ion known as cation while the atom which gains electrons forms a negatively charged ion known as anion.

Metal are very highly electropositive element , hence they lose electrons to form cation while non metals are highly elecrtonegative elements they accept an electron to form anion.

In this reaction each sodium atom loses 1 electron and form cation while oxygen atom gains 2 electron to form anion.

Na loses an electron.

O2 accepts electron