Homework Help: Confused about the nomenclature of this compound (CrO3)

chemist2b · Aug 29, 2012

So i'm a little confused about the nomenclature of this compound (CrO3). is it chromium (VI) oxide? chromic acid? and then Cr2O3 is just plain Chromium (III) oxide right?

AGNuke · Aug 30, 2012

Yes, that's it!

chemisttree · Aug 30, 2012

The oxygens in CrO₃ and Cr₂O₃ each have a formal charge of -2.

Neither of these is chromic acid.

AGNuke · Aug 30, 2012

CrO₃ is Chromium (VI) Oxide or Chromic Anhydride, as if we add water in it, it forms Chromic Acid, which is H₂CrO₄

chemisttree · Aug 31, 2012

AGNuke said: ↑

CrO₃ is Chromium (VI) Oxide or Chromic Anhydride, as if we add water in it, it forms Chromic Acid, which is H₂CrO₄

The equilibrium of aqueous chromium trioxide lies far to the reactants side. Are you saying that aqueous chromic acid contains significant OH-?

AGNuke · Sep 1, 2012

I don't get what you meant. I consulted my teacher and he said that CrO₃ is an acidic oxide, thus it can also be referred to as acidic anhydride.

He also mentioned that H₂CrO₄ is a strong acid, can be considered as an analogue to Sulphuric acid. I can't get what you meant from equilibrium.

See This : Chromium Trioxide