Maine Barber Practice Exam

The most common chemical used for perming hair is ammonium thioglycolate. This chemical is a key ingredient in many perm solutions because it effectively breaks the disulfide bonds in the hair, allowing it to be reshaped into curls or waves. When combined with a reducing agent, ammonium thioglycolate enables the hair structure to be altered temporarily, which is essential for achieving the desired perm style.

While other chemicals listed have their uses, ammonium thioglycolate specifically serves the purpose of perming by providing the right balance of strength and gentleness needed for this hair service. Hydrogen peroxide is primarily used as an oxidizing agent in hair bleaching and coloring processes rather than perming. Sodium hydroxide, while used in some types of relaxers, is not commonly used for perming as it can be much harsher on the hair. Ethanolamine is often found in hair color products but does not serve the primary function of perming. Thus, ammonium thioglycolate stands out as the correct choice for perming hair.