Minnesota Barber State Practice Exam 2025 - Free Minnesota Barber Practice Questions and Study Guide

The main ingredient in most hair relaxers is sodium hydroxide or calcium hydroxide. These chemical compounds are strong alkalis that work by breaking down the disulfide bonds in the hair's keratin structure. This process allows the hair to become more manageable and straight. Sodium hydroxide, often called lye, is especially known for its effectiveness in relaxing tightly curled or coiled hair types; it is a powerful ingredient that alters the pH of the hair, leading to a straightened texture.

Calcium hydroxide is sometimes used in a combination with other ingredients to enhance the relaxing process, particularly in no-lye relaxers, which tend to be less irritating to the scalp. The choice between these ingredients depends on the specific formula of the relaxer and the hair type it is intended for.

The other options, while related to hair care and treatments, do not serve as the primary active ingredients in hair relaxers. Ammonium thioglycolate is typically used in perming solutions rather than relaxing. Glycolic acid is a type of alpha hydroxy acid primarily used for exfoliation and improving skin texture, not for hair straightening. Hydrogen peroxide is a bleaching agent that can lighten hair color but does not have the relaxing