Here's why:
* Pure Substance: A pure substance is made up of only one type of atom or molecule. It has a fixed chemical composition and definite properties. Examples include pure water (H2O) or pure gold (Au).
* Hair Dye is a Mixture: Hair dye contains a complex mixture of various chemicals, including:
* Dyes: To impart the desired color.
* Developers (Oxidizers): To open the hair cuticle and allow the dye to penetrate (e.g., hydrogen peroxide).
* Alkalizing agents: To raise the pH and help the developer work.
* Conditioners and other additives: To protect and moisturize the hair.
* Solvents: To dissolve and carry the ingredients.
Since it's composed of multiple distinct substances that are chemically combined, hair dye is a mixture.
It's a chemical mixture because a chemical reaction occurs during the dyeing process.