Answered by Alana Jensen, Environmental Educator, INL ESER Program
I have so many favorite experiments, but here are a couple of fun ones to do in the summertime.
You will need: Dishwashing soap, glycerin, water, large jar, liquid measuring cup, pipe cleaners, pliers
- Measure the volume of your jar by filling the jar with water and using the liquid measuring cup to measure the water in ounces.
- Decide how much bubble mix you want. Pick a volume slightly less than the volume of the jar.
- The recipe for super bubbles is written in percentages:
– 30% dishwashing soap
– 10% glycerin
– 60% water
For each ingredient, multiply the percentage by the volume you picked. To check you’ve got the correct quantities, add up the volumes in ounces for all three ingredients. They should add up to the volume of bubble mix you picked. See the example above.
- Pour all the ingredients into the jar and mix carefully. We’re ready to blow bubbles!
- Bend the pipe cleaner into a straight line, then bend the end part of the wire into a square. Make sure the square will fit into your jar and that you have some wire coming off the square as a handle to hold with the pliers.
- Use the pliers to dip the square into your bubble mix and pull it out again. There should be a thin film of bubble mix inside the square.
- Softly blow through the film and you should make bubbles. Are they square, like your bubble frame? Bend your pipe cleaner into another shape. What shape are the bubbles?
What’s Happening? Bubbles consist of a thin film of soapy water filled with air. When you blow a bubble, the film expands outward. The forces acting between the molecules of the bubble cause it to form the shape that encloses the most volume with the least surface area — a sphere. That is why all the shapes become a circle.
If you blow a lot of bubbles, you might get two bubbles stuck together. Each bubble will look like a sphere with one flat side. This isn’t a minimal surface for the individual bubbles, but the flat side is shared so there’s actually less bubble film than there would be with two separate bubbles!
Grass and Light
You will need: shallow, rectangular container (the bigger the better), potting soil, grass seed, sun-blockers (coins, rocks, etc.)
- If your container doesn’t have drainage holes, fill the bottom with a layer of gravel. Fill the rest of the container with potting soil.
- Thickly scatter the grass seed over the soil and water as needed until the grass is established.
- Keep the container in a spot that gets plenty of sunlight.
- Once your grass is growing, you need to decide what pattern you want to create. Find sun-blockers that will fit in your pattern. Sun-blockers are dense materials that won’t allow sunlight to go through them. You want to make sure they don’t move around during the experiment, so they need to be quite heavy.
- Arrange your items in the desired pattern and put the container back into the sunlight.
- Wait 5-7 days before removing the items and revealing your pattern. You can check the progress of your pattern by lifting up your objects to peek and see if the grass has changed color.
What’s Happening? The sun-blockers deprived grass of light, which changed its color to pale shades of green, yellow, or white. When deprived of light, chlorophyll, which gives the grass blades their green color, fails to function. When the grass blades don’t produce chlorophyll they lose their green color. As long as you don’t leave your sun-blockers down too long, your design will indeed be fleeting with grass regaining its color within a few days.
With your parents’ permission, you may try this experiment on a larger scale in your backyard.