Chromic acid is used in staining procedures for which purpose?

• A. Oxidation
• B. Reduction
• C. Staining
• D. Mordant

Answer: (A)

Chromic acid serves as an oxidizing agent in staining procedures, not as the dye itself. It oxidizes certain components in the tissue to create reactive groups (such as aldehyde sites) that subsequent staining reactions can target, enabling the color indication produced by the stain. This preparatory oxidation step is the reason oxidation is the best description of chromic acid’s role. It isn’t used to stain directly, nor does it act as a reducing agent or as a mordant in the typical sense.