Commercial deodorant is an example of a colloid called

Analysis

This question tests your knowledge of colloidal systems, specifically the classification of colloids based on the physical state of the dispersed phase and the dispersion medium.

Concept Explanation

A colloid is a mixture where one substance of microscopically dispersed insoluble particles is suspended throughout another substance. We classify them based on what is being dispersed in what:

• Aerosol: A system where a liquid or solid is dispersed in a gas. (Examples: Fog, smoke, hair spray, and commercial deodorants).
• Sol: A system where a solid is dispersed in a liquid. (Examples: Paint, blood, ink).
• Foam: A system where a gas is dispersed in a liquid. (Examples: Whipped cream, soda water).
• Emulsion: A system where a liquid is dispersed in another liquid. (Examples: Milk, mayonnaise).

Step-by-Step Solution

1. Identify the components of a commercial deodorant: A spray-type deodorant consists of fine liquid droplets (the dispersed phase) suspended in a gas (the dispersion medium, which is the propellant).
2. Match with definitions: Since we have a liquid dispersed in a gas, we look for the definition that fits this category.
3. Evaluate the options: • Aerosol: Liquid/Solid in Gas. This matches our deodorant spray. • Sol: Solid in Liquid. Incorrect. • Foam: Gas in Liquid. Incorrect. • Emulsion: Liquid in Liquid. Incorrect.

Conclusion

Commercial deodorants (specifically spray types) are classified as aerosols because they involve the dispersion of liquid particles into a gaseous medium.

Exam Tip

To remember these easily, think of the "medium":

• If it ends in "-sol" (Aerosol), think of the air (gas) as the medium.
• If it is an Emulsion, think of "emulsified" liquids like oil and water.
• If it is Foam, think of the bubbles (gas) trapped in a liquid (like soap suds).