Why do most shampoos contain active ingredients called surfactants?

Why do most shampoos contain active ingredients called surfactants?

• A. To add fragrance
• B. To provide conditioning
• C. To remove oil from the hair (cleansing agents)
• D. To color the hair

Answer: (C)

Surfactants are included in shampoos because they act as cleansing agents by interacting with both water and oil. Their molecules have a hydrophobic tail that sticks to oil and a hydrophilic head that likes water. When you work the shampoo through your hair and rinse, these molecules surround greasy particles and oil to form micelles. The oil gets trapped inside these micelles, which are then rinsed away with water, taking the dirt and oil with them. This action reduces the surface tension between water and oil, helping water wet the hair more effectively and lift away grime. Fragrance, conditioning, and color are separate features; the essential purpose of surfactants in shampoo is to remove oil and dirt from the hair.

Surfactants are included in shampoos because they act as cleansing agents by interacting with both water and oil. Their molecules have a hydrophobic tail that sticks to oil and a hydrophilic head that likes water. When you work the shampoo through your hair and rinse, these molecules surround greasy particles and oil to form micelles. The oil gets trapped inside these micelles, which are then rinsed away with water, taking the dirt and oil with them. This action reduces the surface tension between water and oil, helping water wet the hair more effectively and lift away grime. Fragrance, conditioning, and color are separate features; the essential purpose of surfactants in shampoo is to remove oil and dirt from the hair.