What is the oxidizing agent commonly used in hair coloring?

The oxidizing agent commonly used in hair coloring is hydrogen peroxide. It plays a crucial role in the hair dyeing process by facilitating the chemical reactions required for color transformation. When applied to the hair, hydrogen peroxide acts to lift the natural color, allowing for new color to be deposited.

This process occurs because hydrogen peroxide releases oxygen when it breaks down, which oxidizes the natural pigment in the hair. This oxidation is necessary for the dye to adequately penetrate the hair shaft and provide the desired color.

In contrast, ammonia is used to open the hair cuticle, allowing the dye and oxidizing agent to penetrate; however, it is not the oxidizing agent itself. Water and sodium chloride serve different purposes in hair care and dyeing and do not act as an oxidizing agent.