Which type of waves require heat with tension to process?

• A. Alkaline waves
• B. Acid waves
• C. Neutral waves
• D. Partial perms

Answer: (A)

Alkaline waves use a high-pH reducing solution that opens the hair cuticle and breaks the disulfide bonds quickly. Heat is applied to speed up the chemical reaction and help the waving solution diffuse into the cortex, while tension keeps the hair taut around the rod so the curl forms evenly. This combination—high pH, heat, and tension—is what makes alkaline waves require heat with tension to process. Acid and neutral waves use milder formulas and typically process at room temperature or with less heat, and partial perms refer to a technique rather than a wave type.