Chapter 9: Problem 82
The hair dyes available in the market generally contain two bottles, one containing the dye and the other hydrogen peroxide. Before applying the dye, the two solutions are mixed. The hydrogen peroxide (1) is added to dilute the solution of the dye (2) oxidises the dye to give the desired colour (3) reduces the dye to give the desired colour (4) acidifies the solution of the dye
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Hydrogen Peroxide
In the context of hair dye, hydrogen peroxide plays a critical role. When you mix the dye with hydrogen peroxide, it facilitates the oxidation process necessary to alter the color of your hair. It essentially helps to open up the hair cuticle, enabling the dye to penetrate deeply and offer long-lasting color transformation.
This oxidizing ability means it is predominantly used to ensure the hair dye develops the desired hue on your hair, making it an essential component in hair dye kits.
Here’s a brief overview of hydrogen peroxide’s characteristics:
- Formula: H₂O₂
- Properties: Colorless and slightly more viscous than water
- Uses: Disinfectant, bleaching agent, and an oxidizing agent
Chemical Reactions
When you mix the dye with hydrogen peroxide, several chemical reactions occur, primarily oxidative reactions. In these reactions, hydrogen peroxide donates oxygen atoms, which helps in breaking down the natural color pigments in your hair and facilitates the bonding of the new dye pigments to your hair.
Without these chemical reactions, the hair dye wouldn’t be able to penetrate your hair shaft properly and deposit the color effectively.
Key aspects of chemical reactions include:
- Reactants: Substances that undergo change (e.g., hydrogen peroxide and the hair dye)
- Products: New substances produced from the reaction (e.g., the altered hair color)
- Oxidation: A specific type of reaction where a substance loses electrons
Oxidation Process
In the context of hair dyeing, the oxidation process facilitated by hydrogen peroxide leads to the desired color change in the dye. When hydrogen peroxide oxidizes the dye, it helps to break down the natural color molecules in your hair and enables the new color molecules to bond more effectively.
Some key points about the oxidation process are:
- Involves the loss of electrons from a substance
- Often involves the addition of oxygen or removal of hydrogen
- Crucial for effective hair dyeing, making the dye molecules more reactive and able to bond with hair
The efficiency of the oxidation process is why hydrogen peroxide is such a critical component in hair dye solutions, ensuring a long-lasting and vibrant color in your hair.