Wally Water Experiment Zone
Make it Rain!
This experiment teaches you about the water cycle. It’s a neat trick – you can make it rain without a cloud in the sky!
What you need:
A two-liter plastic bottle
Scissors
Gravel (aquarium gravel works well)
Potting soil
Peat moss
Two buckets
Two scoop-type measuring cups
Seeds (marigolds work well)
Small plants
Water
Plastic wrap
Rubber bands
Now here’s what you do…
1. Use the scissors to cut off the tops of the bottles about two inches down.
2. Mix the potting soil and peat moss in a bucket. Place the gravel in the other bucket.
3. Place about an inch of gravel into the bottle.
4. Place about three inches of the dirt on top of the gravel.
5. Plant a few seeds about one inch below the soil on one side of the bottle. Put the plants about an inch below the soil on the other side.
6. Water the plants and seeds. Make sure to give the plants plenty of water.
7. Seal the bottles by using plastic wrap and the rubber bands.
8. Place the bottle in a windowsill or another sunny location.
9. Watch the bottles over the next three weeks and write down what happens!
What you learned…
After a few days condensation (water drops) appeared on the lid. The condensation made the air in the bottle get saturated with water. Then the water fell from the lid like raindrops onto the plants and soil. Because of the rain, the plants grew!
The key to this experiment is to begin with enough water. By watering thoroughly in the beginning you created enough water to evaporate, condense, and fall onto the plants.
This is how the water cycle works! Mother Nature doesn’t make “new” water every year. We use the same water over and over again. Water falls to the ground as rain or snow; it eventually evaporates back into the air and then falls to the ground again.
That’s why it’s possible to drink water as old as a dinosaur!
What do you See?
Learn a new word with this experiment. Why is water transparent?
What you need:
One or two fish bowls
One or two mirrors
Now here’s what to do…
1. Fill the fish bowls with water (fill them almost to the top)
2. Place the fish bowls on a table.
3. Bend down and look into the bowl. What color is the water? Can you see through the water?
4. Now put a mirror behind each bowl. (Have a friend hold the mirror or prop it up against a wall)
5. Bend down and look into the fish bowl. What do you see?
What did you learn?
You can see through the bowl because water is transparent. That means we can see through it. When you prop the mirror behind the bowl, you can see yourself!
When Will it Spill?
Water has a unique property called “surface tension”. To find out what this means, try the experiment below!
Here’s what you need:
Clear glass
Paper clips
Water
Now here’s what you do:
1. Fill the glass with water until it’s completely full
2. Now predict how many paper clips you can put into the glass until the water spills out.
3. Start placing the paperclips into the glass – make sure to count them as you put them in.
4. How many can you place in the glass before it overflows? How close was your guess?
What did you learn?
The cup can hold hundreds of
paper clips before it overflows! That’s because water has “surface tension”. The water
forms a thin skin, a surface on
top of the water. If you bend
down and look at the glass,
you’ll see the water rise on the
top, but not spill out. That
surface tension keeps the
water from spilling out of the glass.
The Water Parfait
Volume is the amount of space something occupies. Water’s volume, or the space it occupies, changes depending on if water is a liquid, gas or solid.
The weight of substance’s volume is called density. The ability for something to float depends on its volume and its weight. The denser something is, the more likely it will sink.
For example, warm water is less dense than cold water, so it floats on top of it.
Try this experiment to learn about density and what rises to the top!
Here’s what you need:
4 empty glasses (tall)
Cold water
Hot water
Salt
Food coloring (4 different colors)
Here’s what to do:
1. Take four glasses. Put cold salt water in the first, cold water in the second, hot salt water in the third and hot water in the fourth.
2. Add a different color of food coloring to each glass.
3. Take a tall glass and carefully pour the colored water from each glass into it, beginning with the cold salt water and ending with the hot water. Be careful not to mix the layers – pouring over a spoon works well.
What happened?
The cup should have layers of hot water on the top, then hot salt water, cold water and cold salt water. This reinforces the fact that warmer water is less dense than cold water so it floats on top of it. Fresh water floats on salt water, as long as the two don’t mix.
Make a Cloud
There’s water vapor all around us. These simple experiments help explain how clouds form.
First, make some water vapor yourself! Put your hand in front of your mouth and breathe out quickly five times. Now touch your hand. What do you feel? Moisture! You can really see water vapor during cold weather when you breathe.
Now try the experiment below to make a cloud.
Here’s what you need:
Clear, empty glass
Freezer
Oven mitt
Here’s what to do:
1. Put a dry, empty, clear glass into the freezer. Leave it in the freezer for 15 minutes.
2. Remove the glass from the freezer with an oven mitt and breathe gently into the glass.
3. Watch what happens.
What happened?
There’s a “cloud” inside the glass. The cloud formed when the water vapor in your warm breath came in contact with the cold glass surface. This is similar to how clouds form in the sky. Remember, temperatures at higher altitudes can be considerably below zero even when it’s warm on the ground. In the sky, the extra air condenses to form clouds. Water vapor inside the clouds will eventually condense and the water will fall back to the ground as rain, snow or hail.
