How does the addition of a surfactant affect the surface tension of water?
Practice Questions
Q1
How does the addition of a surfactant affect the surface tension of water?
Increases surface tension
Decreases surface tension
No effect on surface tension
Surface tension becomes negative
Questions & Step-by-Step Solutions
How does the addition of a surfactant affect the surface tension of water?
Step 1: Understand that water molecules are attracted to each other due to cohesive forces, which create surface tension.
Step 2: Know that a surfactant is a substance that can mix with both water and oils, and it has a special structure with a hydrophilic (water-attracting) part and a hydrophobic (water-repelling) part.
Step 3: When a surfactant is added to water, its molecules position themselves at the surface of the water.
Step 4: The hydrophilic part of the surfactant interacts with water, while the hydrophobic part tries to avoid water, disrupting the cohesive forces between water molecules.
Step 5: As a result of this disruption, the surface tension of water decreases, making it easier for the water to spread and mix with other substances.
Surfactants and Surface Tension – Surfactants are compounds that reduce the surface tension of liquids by interfering with the cohesive forces between molecules.