4.6.2. Applications of Surface Tension

Try these first

1. 1.

   What is surface tension?

   Hint

   Think about why raindrops form shapes.

2. 2.

   How does temperature affect surface tension?

   Hint

   Recall that heat changes molecular motion.

3. 3.

   What causes surface tension in a liquid?

   • Only cohesive forces
   • Only adhesive forces
   • Cohesive forces exceeding adhesive forces

   Hint

   Think about the structure of liquid surfaces.

4. 4.

   True or False: Surface tension increases with rising temperature.

   • True
   • False

   Hint

   Recall how heating affects molecule interactions.

5. 5.

   Calculate the surface tension exerted by water if a droplet has a radius of 0.5 cm and creates a pressure difference of 0.1 atmospheres on the surface.

   Hint

   Remember the pressure relationship for spherical droplets.

6. 6.

   Discuss the implications of changing surface tension in detergents and its effect on cleaning efficacy.

   Hint

   Consider how dish soap behaves compared to plain water.