Final answer:
The compound formed by magnesium and barium would be metallic because it involves the bonding of two metal elements, unlike ionic compounds which form between a metal and a nonmetal, or covalent compounds which form between nonmetals.
Step-by-step explanation:
The compound formed by magnesium (Mg) and barium (Ba) would be considered metallic because it involves the bonding of two metal elements. Typically, ionic compounds are formed between a metal and a nonmetal, where the metal loses electrons to become a cation, and the nonmetal gains electrons to become an anion. Examples of ionic compounds include KCl and MgCl2. On the other hand, covalent bonds occur between nonmetals, such as in the compounds NC13, IC1, PC15, and CC14. Therefore, when two metals such as magnesium and barium combine, the bond is not ionic or covalent but rather metallic, where electrons are shared in a 'sea' of electrons that flow around positively charged metal ions.