Properties of Water

In this experiment, students investigate the unique properties of water through two engaging activities. The first, “Walking Water,” explores capillary action and how water can travel against gravity due to its cohesive and adhesive properties. Colored water moves across paper towels from full cups to empty ones, demonstrating water’s ability to move through narrow spaces.

The second activity, “Drops on a Penny,” compares the surface tension of water and isopropyl alcohol by counting how many drops can sit on a penny before spilling over. This highlights the electrostatic forces and cohesion of water molecules, showing that water has a much stronger surface tension than alcohol. Together, these experiments provide a hands-on understanding of how water behaves at the molecular level.

Learning Objectives

Students will know

Adhesion
Cohesion
Surface tension
Intermolecular forces

Students will understand

Many of the properties of water (adhesion, surface tension, etc.) are due to strong intermolecular forces.
Not all substances have the same intermolecular forces.

Students will be able to

Perform a “Walking Water” experiment to see how water molecules have stronger adhesion forces to paper than it’s own cohesive force.
Investigate intermolecular strength and surface tension by conducting “Drops on a Penny” with water and alcohol.

Standards Alignment + Connections

Next Generation Science Standards Connections

HS-PS1-3: Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.