Florida Restricted Barber Practice Exam 2025

What is the primary ingredient in most hair relaxers?

1. Calcium hydroxide

2. Sodium hydroxide

3. Ammonium thioglycolate

4. Glyceryl monothioglycolate

The correct answer is: Sodium hydroxide

The primary ingredient in most hair relaxers is sodium hydroxide. This compound is a strong alkali that acts as a pH adjuster in hair relaxers, helping to break down the protein structure of the hair, which ultimately results in a smoother and straighter appearance. Sodium hydroxide is particularly effective for managing curly or tightly coiled hair, allowing for significant changes in texture. In contrast, other options such as calcium hydroxide, ammonium thioglycolate, and glyceryl monothioglycolate can also be found in hair products but are used for different purposes. Calcium hydroxide is often used in combination with other chemicals for certain types of relaxers but is not the primary ingredient. Ammonium thioglycolate is primarily used in permanent waving and is a milder alternative, making it suitable for soft curls rather than straightening. Glyceryl monothioglycolate is also a less aggressive option used in some perm formulations. Understanding the specific functions of these various compounds helps professionals choose the right product for their clients’ hair types and desired results.