Everything Kids' Magical Science Experiments Book by Tim Robinson Read Free Book Online

letter of the next! HINT:Fill the drops in order, even though it sometimes looks as if you are spelling backward.
    Question: Can you make water disappear?
Materials
A few disposable diapers
Water
Measuring cups
Procedure
Open a disposable diaper and lay it flat on a table.
Pour one cup of water into the thick part of the diaper and watch what happens.
Repeat step 2 until no more water can be absorbed. Keep track of how many cups of water the diaper held.
The Science Behind the Magic
    The water doesn't actually disappear, of course. It's absorbed by the material in the diaper. This material is another kind of polymer, called sodium polyacrylate, particles of which are about the size of regular table salt when dry. When the particles get wet, however, they absorb water until they swell to nearly four times their original size. What's more, these particles don't stick together, but remain separate. This provides extra comfort for babies with wet diapers and offers you an interesting extension activity.
Follow-Up
    Take another diaper and with an adult's help, cut it open so you can see the materials inside. Pour these materials into an empty cup, preferably a clear one. Now slowly pour water into the cup and watch how the particles absorb water and grow. Keep pouring water into the cup until all the dry particles are wet. Can you turn the cup upside down without any water falling out? Depending on how much water you poured and how much of the absorbent diaper material you used, you may find that nothing comes out at all. Then, try adding some table salt and mixing with a spoon. You should see the water come back, as the salt reacts with the gel you produced to release the water.
    Did You Know?

    The first disposable diaper can be traced back to the year 1950. Today, nearly 20 billion disposable diapers are used each year in the United States.
    Science Online

    Visit the HowStuffWorks. com Web site to learn more about the magic behind disposable diapers: http://science.howstuffworks.com/ question207.htm.

Science Fair: Changing Water Colors
    Have you ever tried to mix several colors together to make new colors, only to find that you ended up with a dark brown or black mixture? This typically happens when you mix multiple colors together. But sometimes, if you mix the right colors in the right order, you can produce a surprising result that will amaze you.
    Question: Can you mix colors to end up with your original color?
Experiment Overview
    If you were to mix several paint colors together, you would undoubtedly produce a black or very dark brown color. But in this experiment, it's the order in which you mix the colors, combined with the types of liquid you are mixing, that makes the experiment work. Instead of using colored water, you will use grape juice, ammonia, and vinegar. The reactions, completed in the correct order, will produce color changes that end up giving you the same color of liquid that you begin with.

    SAFETY NOTE: Do not drink any of the liquids in this experiment. They may look safe, but can be very dangerous.
    INDICATOR: A liquid that changes color in the presence of an acid or a base.
    BASE: Chemical opposite of an acid. Bases tend to be bitter tasting as opposed to sour-tasting acids. Bases in large concentrations can be very dangerous.
Science Concept
    The key to this experiment is the use of grape juice. Grape juice is an indicator that can tell you whether an acid or base is present. Depending on what kind of liquid you mix it with, it will change colors. When an indicator mixes with a base, it tends to turn green, and when it mixes with an acid, it tends to turn red. The key is trying to understand which of the other liquids is an acid and which is a base.
Materials
3 small drinking glasses
Unsweetened grape juice
Water Liquid ammonia
Vinegar
Measuring spoons
Eyedropper
Procedure
Mix one tablespoon of unsweetened grape juice with about four ounces of water in one of the three glasses. It should have a