Which substance is added to hydrogen peroxide to enhance its chemical action?

Ammonia is added to hydrogen peroxide to enhance its chemical action, particularly in hair color formulations. The primary role of ammonia is to open the hair cuticle, allowing better penetration of the hydrogen peroxide into the hair shaft. This penetration is crucial because hydrogen peroxide acts as an oxidizing agent, facilitating the lightening of hair and aiding in the development of hair color.

By breaking down the hair's natural pigment, ammonia helps create a more pronounced and effective coloring result. This combination is commonly found in various hair color products, improving their efficacy. Other substances listed, while they may have their uses in different applications, do not serve the same purpose of enhancing the chemical action of hydrogen peroxide in the context of hair design.