What is the Difference Between Chromic Acid and Chromium Trioxide?

Chromic acid and chromium trioxide are two related inorganic substances containing the chemical element chromium. The key difference between the two is that chromic acid is a strongly acidic solution containing H2CrO4 molecules, while chromium trioxide is the acidic anhydride of chromic acid.

Chromic Acid:

• Composed of the elements chromium, oxygen, and hydrogen.
• Dark, purplish red, odorless, sand-like solid powder when dissolved in water.
• Features chromium in an oxidation state of +6 (or VI).
• Strong and corrosive oxidizing agent and a moderate carcinogen.
• Can be prepared by the hydration of chromium trioxide.

Chromium Trioxide:

• Inorganic compound with the formula CrO3.
• Acidic anhydride of chromic acid.
• Dark-purple solid under anhydrous conditions and bright orange when wet.
• Powerful oxidizer, mutagen, and carcinogen.
• Mainly used in chrome plating and the production of synthetic rubies.

In summary, chromic acid is a strongly acidic solution containing H2CrO4 molecules, while chromium trioxide is the acidic anhydride of chromic acid and is an inorganic compound with the formula CrO3. Chromic acid can be prepared by the hydration of chromium trioxide.

Comparative Table: Chromic Acid vs Chromium Trioxide

Here is a table comparing the differences between chromic acid and chromium trioxide:

Chromic acid is a strongly acidic solution containing H2CrO4 molecules, and it is prepared from the combination of concentrated sulfuric acid and dichromate. Chromium trioxide, on the other hand, is an inorganic compound with the chemical formula CrO3 and is the acidic anhydride of chromic acid. The key difference between chromic acid and chromium trioxide is that chromic acid is a strong acid, whereas chromium trioxide is the acidic anhydride of chromic acid.