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Water. It’s one of the basic elements of life. Living things need it every day to survive. It seems that water is everywhere and in all facets of life. We drink, bathe, and play in it. Sometimes, we take it for granted.

Since water is everywhere, let’s learn more about the properties of water and test them with a few simple experiments.

The Properties of Water

The Water Molecule

Scientifically speaking, water is a cool molecule to study.

Water is a polar molecule. Even though water is a neutral molecule in that it has an equal number of protons and electrons, there is an uneven electron distribution within each water molecule that makes it polar.

The oxygen atom in a water molecule attracts electrons more strongly than hydrogen does. This means that electrons tend to be at the oxygen end of the molecule. This makes the oxygen end of the molecule slightly negative. Thus, the hydrogen end of the molecule is slightly positive.

This polarity of water gives it some special properties, like cohesion and adhesion, that you can easily demonstrate right in your kitchen.

Cohesion Properties of Water

Cohesion simply means that water molecules like to stick to each other. This is caused by the slightly negative charge of the oxygen atom of one water molecule being attracted to the slightly positive charge of the hydrogen atoms of another water molecule.

Surface tension is a good example of cohesion at work. Have you ever seen a water skipper “skate” across the water of a pond? This insect literally walks on water because it takes advantage of the surface tension of water. Water molecules hold together tight enough to let these insects stay on top of the water.

You can test surface tension by filling a glass with water and gently laying a needle on the surface of the water using a fork. Since the needle has a higher density than water, it will sink if just dropped in the water. However, if the surface tension is not broken, the needle can be placed on the water in such a way that the surface tension of the water holds the needle on the surface.

Cohesion can also be tested by filling that same glass of water to the top and then gently adding more and more water until the water is actually forming an arc of water slightly over the top of the glass. The cohesive properties of the water are holding the molecules together so that they will not spill over the top of the glass. The weak hydrogen bonds between the water molecules will eventually give way.

Adhesion Properties of Water

Water molecules are attracted to each other (cohesion). They are also attracted to other charged molecules. This is adhesion. You can see this when it rains and water drops form on windows. These drops should be pulled to earth by gravity, but the force of the adhesion of water to that surface is stronger.

You can test adhesion by dipping a paper towel into a small bowl of water and food coloring. Watch the colored water as it climbs up the towel against gravity. Once again, the water molecules are drawn to other molecules and overcome the force of gravity.

What ways can you and your kids think of to test cohesion and adhesion?

Properties of Water Worksheet

Download this free worksheet to use in your water lesson and record your experiments.

This inexpensive book is probably available at your local library or on Amazon if you are looking for more water experiments and homeschool lessons.

Learn more about water…

• Learning About the Water Cycle
• Sink or Float Experiment
• Summer Cloud Science

By contributing writer Marci

Fireflies, lightning bugs, whatever you call them, they have fascinated me since I was little. Those little dots of light slowly rising and then disappearing in the low light of dusk. It is like magic sprinkled with fairy dust for a young child.

We used to run through the yard capturing lightning bugs in quart jars. In my young mind, the bigger the jar, the better. My mom would poke holes in the top of the jar so our little guests would have some air. I always put my jar of light on my bedside table so I could watch the light show as I fell asleep.

Whether your kids are like I was or not, you can help them learn more about fireflies with these interesting firefly facts and a fun firefly craft that even older kids enjoy.

Where to Find Fireflies

There are 2000 species of lightning bugs on all continents except Antarctica.  Chances are, you have lightning bugs where you live.

Firefly Larvae

These bugs like warm, humid areas. Their larvae live on rotting wood and plant matter near the water’s edge. The adults only live a few weeks and can be found in the forest as well as in tall grass where they can hide during the day.

Firefly Facts

• Fireflies use their light to attract mates and to communicate with other fireflies
• The light of the firefly is the most efficient light in the world. 100% of the energy involved is emitted as light. Compare this to an incandescent light bulb that emits only 10% of its energy as light and the rest as heat. Fluorescent bulbs are us 90% of their energy as light.
• Firefly larvae eat snails, worms, and other insects. The adults may eat nothing because of their short lifespan.
• Adults live a few weeks. It’s just long enough to mate and lay eggs. Larvae live one year.
• The glow of a firefly is a bioluminescent chemical reaction.
• Fireflies can be poisonous.

Firefly Craft

Even my 10 and 14 year old had fun creating their own bugs with this firefly craft.

Supplies Needed

• Plastic Easter eggs
• Pipe cleaners/chenille
• Plastic eyes
• Paper or other material for wings
• Battery-operated tea light

Instructions

1. Cut the chenille into lengths for the antennae and 6 legs.

2. Poke small holes into the eggs where the antennae and legs should go. We used a thumbtack for this. Insert the wires into the holes.

3. Glue eyes and wings onto your firefly.

4. Open up the egg and place the battery operated tea light inside.

You’ve got a firefly!

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• How to Host a Family Weenie Roast
• Bug-Themed Worksheets
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