* Sodium (Na): This is the metal cation with a +1 charge.

* Bromate (BrO₃⁻): This is the polyatomic anion, formed from bromine (Br) and oxygen (O). It carries a -1 charge.

Since the charges balance out (+1 and -1), the formula for sodium bromate is NaBrO₃.

Note: While chlorine and bromine are in the same family (halogens), the formula of their oxyanions is not identical. The charges and bonding structures of these polyatomic ions differ.