Illustrated Glossary of Organic Chemistry

Chromium trioxide (CrO3): A molecule containing one Cr6+ atom having three double bonds to oxygen atoms. A strong oxidizing agent used to form certain other common oxidizing agents such as Jones reagent and PCC.


Molecular structure of CrO3.

CrO3  +  H2SO4  +  H2O  + acetone

aq. H2CrO4 (Jones reagent)
Mixing CrO3 with concentrated H2SO4, water, and acetone forms aqueous chromic acid (Jones reagent).

CrO3
+

+
aq. HCl

(PCC)
Mixing CrO3 with pyridine and hydrochloric acid forms pyridinium chlorochromate (PCC).