The New Jersey Pinelands has very sandy soils. Under the soil is a vast underground water supply named the Cohansey Aquifer. Pollution of the aquifer can happen if people are not careful about how they dispose of oil, pesticides, or other things that we use.
This experiment will show you how fast pollution can enter the aquifer. After you try it with sand, use some soil that is not sandy and you should see a difference.
Materials that you will need:
Two coffee cans (have you r dad or mom punch holes in the bottom of one of the cans)
One round coffee filter
Enough sand to fill up three-quarters of one of the coffee cans
Enough water to almost fill the other coffee can
Vegetable food coloring (a dark color is best)
A watch that has a second hand
Put the coffee filter in the bottom of the can that your dad or mom punched the holes into. Fill it up three quarters of the way with sand. Pour water into the second can and add the vegetable coloring to the water.
Hold the can with the sand over a sink and pour the colored water into it. Have you parents or brother or sister time how long it takes for most of the water to drip out of the can with the watch. When the water drips slowly (five or ten seconds between drips), write down how many minutes and seconds it took for most of the water to come out of the can. Is it still dark colored?
Now try the same experiment with soil that is not sandy. Does it take less or more time for the colored water to come out of the can?
As you now know, sandy soil allows the water to run out of the can quickly, and the dark color, or "pollution" is still there. If you did this on the ground with the sandy soils that cover the Pinelands, the pollutants could go into the underground water supply and make it undrinkable. Even if the experiment took longer with the soil that was not sandy, pollution will still enter underground water supplies. It will just take more time.
Did you ever see a movie or cartoon with a mad scientist pouring smoking acid onto a metal plate, and the acid eats away at the metal? We hope you know that you should never play with a can or bottle that says it has strong acid in it because it will cause you harm.
All things that are acid, however, aren't really that strong. Soils and water within the New Jersey Pinelands are characterized as being "acidic" meaning that they are the opposite of being "alkaline." Our water doesn't smoke and it isn't even bitter to the taste. In fact, it has won national awards for tasting very good and not containing impurities. It just contains more acid than water in most other places. Our plants and animals are adapted to these acid conditions. It is important for us to protect the Pinelands so that the water will always be pure and not polluted.
The measurement that scientists use to find out if something is acid, neutral, or alkaline is called "pH." A pH of 7.0 is a neutral reading. A pH of less than 7.0 means something is acidic, while a reading of more than 7.0 means something is alkaline. Scientists often use sophisticated instruments to measure the exact pH of a substance. You can find out if something at home is acidic or alkaline by doing the following experiment.
Materials that you will need:
A red cabbage (you can go with mom or dad to get one at the supermarket)
A pitcher of hot water (you should let mom or dad prepare the hot water)
A tablespoon of baking soda
A tablespoon of lemon juice or 1/4 of a glass of lemonade
A tablespoon of milk of magnesia or a similar remedy for acid indigestion (please make sure mom or dad are present when getting and using the milk of magnesia)
Three cups or small jars
A kitchen knife
Have your mom or dad cut up about one cup of the red cabbage into one inch square pieces and place then in one of the bowls. Next have one of your parents poor the hot water into the bowl to soak the pieces of cabbage. Let the water cool and wait for it to turn purple. Your family can use the rest of the cabbage for salad one night, or you can feed it to a rabbit if you have one.
After the water has turned purple, hold the strainer over the second bowl and separate the water from the cabbage by pouring it through the strainer. Pour the purple water back into the empty pitcher. Now you are ready to conduct your experiment.
First, put some lemon juice in a glass. Then, pour a little clear tap water into the second glass, add the baking soda and stir. In the third glass, stir a little clear tap water in with the milk of magnesia. Line up your glasses and fill them half way with the purple cabbage water.
If everything has worked properly, the purple water has turned different colors. If it has become pink (as in the lemon juice), it means that the juice is acidic. If it has become blue or green (as in the baking soda and milk of magnesia), it means they are alkaline. Remember, pink is acidic and blue and green are alkaline.
Now you can test lots of things in your house like orange juice or other liquids you drink to see if they are acidic or alkaline. Your mom or dad may want you to try to test the soil in your garden because plants often require soil conditions that are neutral - not acidic or alkaline. Just put some soil in a cup with some clear water, let it sit for awhile, and pour in the cabbage water. If the color stays purple, the soil is neutral. If it becomes pink or blue, your parents will have to add something to the soil to make it less acid or less alkaline. The people at the local garden center will tell them what to add.
Scientists also use "litmus paper" to do what you just did with the purple water. If you have some purple water left over, you can make your own litmus paper. Just cut some four inch strips of white blotting paper, put them in a dish and pour the purple water on them. When they have become soaked in the liquid, take them out and let them dry. When you want to test something for acidity or alkalinity, dip the purple paper into it. The paper will turn pink, blue or green just like the purple water did. This way you don't need to go out and buy red cabbage every time you want to conduct this experiment.
Good luck with your experiments.