Take into account that oxygen has a negative 2 charge (O-2) and there are 3 of them; therefore, to form this compound Cobalt must have a positive 3 charge (Co3+) because there are 2 of them.
The name of this compound is Cobalt (III) oxide or Cobaltic oxide.
cadmium oxide
Barium Dichloride is NOT correct. The name is Barium Chloride it is a binary ionic compound.
Sodium Bromide
The name of the compound with the formula Cl3N7 is trichlorine septnitride.
Bromine Pentaiodide
Binary ionic compounds are named by writing the name of the action, followed by the name of the anion. Potassium bromide is an example of an ionic compound.
cadmium oxide
Tritechnetium tetraphosphide
Tin Oxide
silver chlorate
Lithium nitride
Aluminum Sulfide
silver(I) chloride
Strontium Selenide
cation
electronegative
cation (apex)