Water has properties of cohesion, adhesion, and surface tension. Cohesion and adhesion refer to the attraction of water molecules to each other and to other substances. This "stickiness" is why water forms droplets and is able to climb surfaces. Surface tension occurs when water molecules at the surface are attracted equally in all directions, forming a spherical shape. Buoyancy allows objects to float because water exerts an upward force opposing the object's weight. These properties are important for living things and technologies that use water.

1. Properties of Water
School/program name
Date

2. Background Information
(for facilitator)
• Cohesion: Water is attracted to water.
• Adhesion: Water is attracted to other substances.
• Adhesion and cohesion are water properties that affect every water molecule on earth and also the
interaction of water molecules with molecules of other substances. Essentially, cohesion and
adhesion are the "stickiness" that water molecules have for each other and for other
substances. Water drops are composed of water molecules that like to stick together, which
explains why water falls from the sky as raindrops rather than individual molecules. Rain therefore
is an example of the property of cohesion. When one corner of a piece of paper towel is dipped
into a glass of water the water will climb the fibers of the paper. The water molecules are attracted
to the molecules of the fabric with greater force than gravity and therefore are able to climb up the
paper. Therefore adhesion is when water molecules are attracted to another surface.
• Surface tension is caused by the attraction of the particles at the surface layer by the quantity of
the liquid. For water, surface tension happens when a water molecule is surrounded on all sides by
other water molecules, which creates a sphere or ball. In the case of surface tension, cohesion is
affected by the volume of water at the surface layer resulting elastic like force. The helps to explain
why some small insects, like a water strider, can walk on water. In the case of a water strider the
weight of the insect is less than the force necessary to penetrate the surface of the water.
• Buoyancy is an upward force exerted that opposes the weight of a fully or partially immersed
object. If the upward force exerted is equal to or greater than the density of the immersed object
the object is deemed buoyant. This is the principle that allows large cruise ships and fishing vessels
to remain afloat even though individual pieces of the vessel would sink if not part of the whole.

3. Agenda
Opening (30 minutes)
Setting the Stage (20 minutes)
Activity: Camp Song, “Little Water Molecule” (10 minutes)
Cyber Investigation: Just Dunk It (15 minutes)
Setting the Stage (15 minutes)
Activity: Cohesion and Surface Tension of Water (60 minutes)
Break (15 minutes)
Cyber Investigation: Sea Trials (15 minutes)
Lunch (30 minutes)
Recess: Water Sponge Relay (30 minutes)
STEM-tastic Careers (30 minutes)
Mind Snacks (15 minutes)
Engineering Challenge: Boat Building Challenge (75 minutes)
STEM Camp Notebook Reflection (20 minutes)
Wrap Up (10 minutes)
Dive Into Digital Project (60 minutes)

4. Learning Objectives
To explain the basic chemistry of water
To investigate properties of water
including cohesion and adhesion

5. Today’s Vocabulary
Surface Tension
Molecule
Volume

6. Setting the Stage

7. Water
Properties
Quiz

8. Activity:
Camp Song
“Little Water Molecule”

9. Cyber
Investigation:
Just Dunk It
Exploration: Just Dunk It

10. Setting
the
Stage
Reading Passage – Getting to know Properties of Water

11. Activity:
Cohesion and Surface
Tension of Water
Hands-On Lab: Cohesion and Surface Tension of Water

12. Cyber
Investigation:
Sea Trials

13. STEMtastic Careers
aquacultural manager
aquarist,
Hydrologist,
water and liquid waste treatment
plant operator
chemical technician
chemist
ship and boat captain
computer software engineer
Economist,
remote sensing scientist
biochemical engineer
hydroelectric plant technician
materials scientist

14. Mind Snacks

15. Engineering Challenge:
Boat Building
Engineering Project: Boat Building Challenge

16. Notebook Reflection
What have you learned about the properties of water?
How do the properties of water impact living organisms?
What is your favorite water activity? How does it relate
to the properties of water?
Which careers you examined today most intrigue you
and why are you interested in them?

17. Wrap Up

18. Water
Properties
Quiz

19. Exploration: Waters of the Earth