Hair is most efficiently "permanently" dyed by

Question

Quizplus · Accepted Answer

Adding colorless reactants that react in the hair to form the desired color is the most efficient method of permanently dyeing hair. This is because the reactants penetrate the hair shaft and chemically bond with the hair fibers, providing a long-lasting color that doesn't fade easily. Soaking hair in colored dye or using water-soluble dyes does not provide a permanent color as the dye simply coats the outer layer of hair and is easily washed away.

Hair Is Most Efficiently "Permanently" Dyed by