Relaxers that contain two components and must be mixed immediately prior to use are called

• A. Guanide hydroxide relaxers
• B. Sodium hydroxide relaxers
• C. Potassium hydroxide relaxers
• D. Lithium hydroxide relaxers

Answer: (A)

Two-component relaxers are designed so the active relaxing agent is formed only when the two parts are mixed just before use. In guanidine hydroxide relaxers, one component provides guanidine carbonate (or a related guanidine compound) and the other provides a base such as calcium hydroxide. When these are combined with water, they react to form guanidine hydroxide in the mix, which is the chemical that relaxes the hair. Because the active ingredient is created at the moment of use, these products must be mixed immediately prior to application.

The other options are single-component formulations that come ready to apply and do not require mixing. They rely on bases like sodium hydroxide, potassium hydroxide, or lithium hydroxide to achieve the relaxing effect, and they don’t involve the in‑situ formation of an active compound at mixing time.