West Virginia Barber Practice Exam

The primary ingredient in most hair relaxers is sodium hydroxide. This chemical is known for its strong alkaline properties, allowing it to effectively break down the protein structure of the hair, which in turn relaxes and straightens it. Sodium hydroxide is often used in formulations intended for more resistant hair textures, as it is particularly effective at altering the hair's natural curl pattern.

In contrast, while substances such as calcium carbonate and potassium hydroxide appear in hair care products, they are not the primary ingredients in relaxers. Calcium carbonate is typically used as a filler or buffering agent, and potassium hydroxide is used in some formulations but is less common than sodium hydroxide. Similarly, ammonium thioglycolate serves as a chemical straightener, but it is primarily used in perm solutions rather than traditional hair relaxers. Thus, sodium hydroxide is the preferred and most commonly used component in many hair relaxer products.