* Ionic compounds form between metals and nonmetals. Barium (Ba) is a metal, and acetate (CH3COO-) is a polyatomic ion containing both carbon and oxygen (nonmetals).

* Covalent compounds form between two or more nonmetals.

* In barium acetate, the barium atom loses two electrons to form a Ba²⁺ cation. The acetate ion (CH3COO-) carries a -1 charge. These opposite charges attract, forming an ionic bond.

Therefore, barium acetate is an ionic compound.