Nevada State Board of Cosmetology Practice Exam

The function of pH in hair care products is crucial for maintaining the hair's natural balance. Hair and scalp have a natural pH level that typically ranges from 4.5 to 5.5, which is slightly acidic. This acidic environment helps to keep the hair cuticles closed, preventing damage and moisture loss, while supporting the overall health of the hair and scalp.

Formulating hair care products with a pH that aligns with this natural range helps to preserve the integrity of the hair. Products that are too alkaline can cause the cuticle to lift, leading to frizz, dryness, and potential breakage. On the other hand, products with a pH that is ideally suited to hair can enhance shine, manageability, and overall texture.

The other choices do not accurately address the primary role of pH in hair care. Changing hair color is more related to chemical reactions within hair dye products, adding fragrance pertains to scent enhancements, and clarifying scalp health focuses on cleansing rather than pH maintenance.