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FUN PROJECTS WITH WATER
WATCH PLANTS REMOVE SUBSTANCES FROM WATER
Water carries many substances. Some materials dissolve in water and cannot be seen while other materials, such as sediments, are carried in suspension (small particles floating around). Some things carried by water are good for plants and animals. Dissolved calcium helps marine organisms build shells. Other substances in the water may be harmful, such as pesticides, heavy metals, oil and other wastes.
What you will need: a few stalks of celery, glasses or jars, and food coloring
What to do:
Add several drops of food coloring (represents pollution by a toxic substance) to water in a jar.
Cut off the bottom of the celery stalks (represent wetland plants, such as cattails, sedges, grasses) and place them in the jars overnight.
Observe the celery on day 2 to see that the colored water has visibly soaked up (called osmosis) into the stalks. If the dye is not visible on the outside of the stalk, break it open to see the coloring inside the plant tissue.
SALT WATER TRICK
It's amazing, but not all water is the same. For example, salt water is heavier than regular fresh water and here is how you can prove that fact.
You will need:
Two drinking glasses
Water
Salt
Two Eggs
Fill the two glasses about 3/4 full with water. In one glass add salt, about 1/4 of a cup should do it. Stir the salt into the water well. Now crack an egg and pour it into the salt water, do the same in the plain water. Wow, the egg sinks to the bottom of the plain water but it floats in the salted water.
Why does this happen?
The salt makes the salted water heavier than the plain water. The egg is then lighter than the salt water and floats on it.
CREATE A SPONGE GARDEN
You will need:
A nice new sponge
Mustard seeds (the ones from the spice section of the grocery store)
Plastic Wrap
Mister (or use a clean spray bottle with water in it)
Soak the sponge in water and then squeeze it. The sponge should be wet but not dripping. Put the sponge on a plate and sprinkle the seeds all over the top. Each night cover the plate with a plastic wrap to keep the sponge moist and during the day unwrap it and put in a place with lots of sun. Spray the sponge each day with the mister to keep it moist.
After several days the seeds will grow and soon you will have a sponge garden. You can even eat the spicy little mustard plants if you would like.
Why does this work?
How can seeds grow without any soil, well a seed is made up of a whole tiny little plant called an embryo and all the food it needs to get started. It's all wrapped up inside the seed coat. In order to sprout all they need is water, sun and the right temperature.
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