Baking Soda Bubbles

Materials

1. 1/4 cup of baking soda  
2. 1 cup of vinegar
3. Bubbles and a bubble wand (you can get this at most toy stores)
4. 2 large, clear containers, like a clear plastic or glass bowl
5. Small clear cup
6. Bowl
7. Spoon

Instructions

1. Put 1/4 cup baking soda in a clear container.
2. Then add 1 cup of vinegar.
3. The mixture of vinegar and baking soda will bubble. It's making carbon dioxide.
4. Blow some bubbles into the container and watch how they float on the carbon dioxide. The bubbles are floating where the carbon dioxide and air meet.

Explanation

1. The carbon dioxide stays at the bottom of the bowl because it is more dense than the air in the bowl. The bubbles float on top of the carbon dioxide because they are filled with air and the air is less dense than the carbon dioxide.
2. This will help explain what density means. Pretend that you had two balloons and you filled one with air, and the other one with the same volume of carbon dioxide. The balloons would be the same size, because the gas in them takes up the same amount of space.
3. But, if you weighed both balloons, the one with the carbon dioxide would be heavier. This means that it's denser than the balloon with air in it.
4. If you still don't understand density, don't worry. There are lots of people out there who can answer your questions. Talk to your teacher, go to a science museum, visit your local library, or ask your parents.

Harry Potter and the Levitating Orb

Wingardium Leviosa! Have you ever wondered how the wizards in Harry Potter were able to make things levitate at the command of their wands? Though many of us, unfortunately, do not have the power of magic, we do have science that can make help us make some fantastic things happen! Check out the quick and easy experiment below to find out how you can impress your friends with the simple magic of science.

Materials:

• 1 inch (2.5 cm) wide PVC Pipe about 24 inches (60cm) long (alternate to this can be a balloon but best results are with a PVC Pipe)
• Mylar tinsel from Christmas trees (recommended to find no thicker than 1 mm in width. Thinnest and most narrow tinsel should be used for best results.)
• Head full of good, dry hygienic hair
• Scissors
• Ruler

Procedure:

1. Gather 6 strands of mylar together and tie them in a knot. Make sure the knot is near the end of the mylar strand. The knot should be approximately 1 inch from the end. Ask an adult if you need help with this step.
2. Tie another knot in the same manner approximately 6 inches (15 cm) from the first knot. Again, the knot should be approximately 1 inch from the end of the mylar bundle.
3. If necessary, cut off any extra mylar off the end of the knots.
4. Now it’s time to charge your PVC pipe. Rub the pipe back and forth on a head full of clean, dry hair for at least 20 seconds.
5. Hold the mylar orb by the knot and hold it over the now charged PVC pipe.
6. Drop the mylar orb directly on top of the PVC pipe.  
7. The orb should repel from the charged pipe. Keep the pipe under the orb and try to move it around. Now you have a levitating orb under the control of your wand (PVC pipe)! If the orb sticks onto the PVC pipe, the mylar tinsel is mostly likely too thick. Try obtaining a thinner kind and perform the experiment again.

Note: The PVC pipe will need to be recharged each time you wish to levitate the orb.

What Happened:

The scientific phenomenon that is occurring in this experiment is called static electricity. In this case, “charging” the PVC pipe by rubbing it on your head makes the pipe have a negative charge. The orb has a positive charge at first, as seen when the orb is dropped on the pipe, the instantly gains a negative charge once it touches the pipe. Right after this, the pipe and orb have negative charges. Same charges make two things repel and this repulsion is what makes possible the orb to levitate upon contact with the pipe. In addition, the orb becomes a ball shape after encountering the pipe because the charged orb has strands that all have negative charges and would like to be as far as possible from each other.

For more information on this experiment, such as videos and where to find materials, or other fun experiments check out: ScienceBob.com 

Happy levitating!