Formula of Ammonium Acetate

[Christiano]

In the formula of Ammonium Acetate, CH3COONH4 (Ammonium - NH4 +) (Acetate - CH3COO -),  The rule of writing forumula says the positive ion is written first. Why isn't ammonium written first in this formula?

[Twenty10]

Coz when you draw the molecule out the NH4 bonds to the O.

[Christiano]

Thanks. I picked this problem up in a practice exam when writing compounds, how do you know if a compound does not follow the standard rule of placing the positive ion first?

[Potter]

Thanks. I picked this problem up in a practice exam when writing compounds, how do you know if a compound does not follow the standard rule of placing the positive ion first?

Afaik, the carboxylate ions are the only exceptions in vce and I think that examiners would accept NH4CH3COO or CH3COONH4.

[Christiano]

Thanks for the heads up