Question

which formula is an ionic compound?
naf
n₂
no₂
co₂

Explanation:

Ionic compounds are formed by the transfer of electrons from a metal to a non - metal. Na (sodium) is a metal and F (fluorine) is a non - metal. In NaF, Na donates one electron to F to form \(Na^{+}\) and \(F^{-}\) ions which are held together by ionic bonds.
\(N_{2}\) is a non - metal element (diatomic molecule of nitrogen, held together by covalent bonds within the molecule). \(NO_{2}\) (nitrogen dioxide) and \(CO_{2}\) (carbon dioxide) are covalent compounds as they are formed by the sharing of electrons between non - metal atoms (N - O and C - O respectively).

Answer:

NaF