Arsenate has more oxygen atoms than sulfate.
Arsenate has a greater negative charge than sulfate.
When arsenate and aluminum bond, the chemical formula is AlAsO4.
Nitride and arsenate have the same charge.
Monatomic anions are usually gases.
Ionic metals tend to end with the suffix -ide.
Since ammonium's atoms are all gaseous, it is a binary covalent compound.
Almost all ionic compounds have metals
Oxide, Acetate, Oxalate, Tartrate
Bromite, Hypobromite, Perbromate, Bromate
Hypochlorite, Chlorite, Perchlorate, Chlorate
Thiocyanate, Hypochlorite, Arsenate, Dichromate
None of the above