A2oz

Does soap increase surface tension?

Published in Science 2 mins read

No, soap decreases the surface tension of water.

Soap is a surfactant, which means it reduces the surface tension of a liquid. This happens because soap molecules have a special structure: one end is attracted to water (hydrophilic) and the other end is attracted to oil and grease (hydrophobic). When soap is added to water, the hydrophobic ends of the soap molecules gather at the surface of the water, pushing the water molecules apart. This weakens the forces that hold the water molecules together, lowering the surface tension.

Here are some practical examples of how soap decreases surface tension:

  • Bubbles: Soap allows bubbles to form because it reduces the surface tension of the water, making it easier for the water to stretch and form a thin film.
  • Cleaning: Soap helps to remove dirt and grease by lowering the surface tension of water, allowing the water to penetrate the dirt and grease more easily.
  • Washing: Soap helps to remove dirt and grime from clothes and dishes by reducing the surface tension of water, allowing the water to penetrate the dirt and grime more easily.

Related Articles