Alaska Hairdresser and Barber Certification Practice Exam

Sodium hydroxide is commonly used in hair relaxers to alter the hair's natural texture. This ingredient works by breaking down the protein structure of the hair, specifically the disulfide bonds found in keratin. By targeting these bonds, sodium hydroxide effectively straightens curly or wavy hair, making it smoother and more manageable. The use of sodium hydroxide is particularly significant because it provides a strong and permanent change in the structure of the hair, unlike some other ingredients that might only temporarily alter the appearance. This is why it is a preferred choice for professional hair relaxers, as it delivers visible and long-lasting results. In contrast, while hydrogen peroxide is used as a bleaching agent and ammonia can serve as a pH adjuster in some chemical processes, they do not perform the specific function of permanently changing hair texture in the manner that sodium hydroxide does. Alcohol, on the other hand, is often used in hair products for its solvent properties and to help in product application, but it does not have any effect on hair texture.