Multiple choice

Chemically indigo is a

  1. Vat dye

  2. Acidic dye

  3. Basic dye

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Indigo is chemically classified as a vat dye. Vat dyes are insoluble in water, require reduction (vatting) to become soluble and penetrate fibers, then oxidize back to insoluble form. This gives indigo excellent colorfastness. Acid dyes need acidic medium, basic dyes need basic medium - indigo doesn't require these conditions.

Keep practicing — related questions