Everything Kids' Magical Science Experiments Book Read Online Free PDF

magically went out!You didn't blow on it, and in fact, it looks like nothing happened to it—it just went out on its own. But there's a science secret behind what's happening here. You see, when baking soda comes into contact with vinegar, a chemical reaction occurs. That's what causes the bubbles and foam you see. This reaction produces carbon dioxide, a gas you can't see or smell and the same gas you find in the bubbles in a can of soda. Carbon dioxide is heavier than air, which means it tends to fall down through the air toward the ground. What you did by “pouring” the large glass into the glass containing the candle was allow the carbon dioxide to escape from the reaction taking place in the large glass. It fell into the smaller glass, surrounded the candle, and caused it to go out.
Follow-Up
    What's great about this experiment is that it is so easy to do over again. Go ahead and try it again! You might need to clean out the large glass and start with fresh vinegar, but each time you do, the results should be the same.
    However, there is another way to blow out a candle without blowing directly on it. To do this, you need to place the lit candle flat on the table, and place a cylindrical object (such as a can of soda or a can of frozen juice concentrate) directly in front of the candle. All you need to do is blow toward the can—the candle behind it should go out. How is this possible? The air isn't blocked by the can. Instead it splits, passes around it on either side, meets up again on the back side, and blows out the candle. Try this with different candles, and objects of different shapes in front. Why does a cylinder seem to be the shape for blowing out the hiding candle?
    Did You Know?

Most of the air you breathe out is carbon dioxide.
Carbon dioxide in its solid state is called dry ice. At room temperature, it changes from a solid directly to a gas though a process called sublimation. This gas appears as a fog and is commonly used in Halloween decorations.
The average tree in a backyard removes 330 pounds of carbon dioxide from the air each year, while producing 260 pounds of oxygen.
Burning at Both Ends
    Question: Can you make a seesaw out of a candle?
    KIDS' LAB LESSONS

Experiment Overview
    Most people, when asked to imagine a seesaw, conjure up images of a playground with children sitting on either end of a large toy, bounding up and down, squealing with joy. For most people, and perhaps for you, this is their only experience with a seesaw. But in this experiment, you will be building your own seesaw, one that needs no outside help to keep rocking back and forth, can fit on your kitchen table, and is definitely not something children should be riding.
Science Concept
    When a candle burns, it loses some of its wax, which melts and sometimes drips over the side. This can produce a big mess if it goes unnoticed, but in this case, that dripping is exactly what you want to see happen. You'll have to trim the bottom end of the candle, so that there is a wick on either end. Then, after you set up your balanced seesaw and light each end, the candle should rock back and forth as long as there is wax left to burn.
Materials
Long (10-inch) taper candle
Kitchen knife (to be used only by an adult)
Ruler
2 straight pins
2 identical drinking glasses
2 small saucers
Matches
Adult partner
Procedure
Ask your adult partner cut about ½ to 1 inch off the bottom of the candle so that the wick is visible. It should stick out of the bottom just like it does the top.
Using the ruler, find the center of the candle and push one pin into each side of the candle at that point.
Carefully rest the pins on each glass so that the candle balances. It might take a few tries to get it just right. It should rock back and forth slowly.
Place one saucer under each end of the candle.
Light one end of the candle and let it burn until it starts to drip. When it does, light the other end and watch the candle begin to rock back and