* Sodium (Na) is an alkali metal, and it always forms a +1 charge as an ion (Na⁺).

* Bromine (Br) is a halogen and typically forms a -1 charge as an ion (Br⁻).

To form a neutral compound, you need one sodium ion (Na⁺) and one bromide ion (Br⁻). This results in the compound NaBr, which is ionic.

Ionic bonds occur between a metal and a non-metal. The metal loses electrons to form a positive ion, and the non-metal gains electrons to form a negative ion. These oppositely charged ions attract each other, forming an ionic bond.