One of my goals with these science videos is to provide support to the homeschool community. After years of writing the Experiment of the Week, and presenting science shows for homeschool groups, I have been impressed with how strongly homeschool families are involved with hands-on science. I have also seen the need for a science curriculum that fulfills their educational needs. Starting with these videos, I hope to offer the homeschool community some of the science education support that they need, as well as a fun way to get students involved with scientific discovery.
I also try to use activities that involve common items. Most homeschoolers don't have access to test tubes, flasks, chemicals, microscopes and other scientific equipment. In the future, I hope to be able to guide them to inexpensive sources for science equipment to enrich their science curriculum.
If you ever watch crime shows, you have probably seen them dusting a crime scene for fingerprints. If you want to try it yourself, you can, with a little science.
For this experiment, you will need:
- a candle
- a water balloon
- a small paintbrush (Either an artists brush or an old make-up brush. The softer, the better)
- some clear tape
- a drinking glass
To collect a fingerprint, first we need to make some fingerprint powder. To do that, simply redo experiment video #3, Heating a Balloon. As you heat the balloon over the candle, you will notice black stuff forming on the balloon. That black stuff is carbon, and it will serve as our fingerprint powder.
Wipe the drinking glass with a soft cloth to remove all the fingerprints. Now use your bare hand to pick up the glass. Place the glass on a sheet of paper, to catch the excess powder. Use the paintbrush to collect some of the carbon powder from the balloon, and GENTLY brush it across the glass. Dip the brush into the carbon frequently as you brush the surface of the glass. Watch for the fingerprints to appear. You can collect the fingerprints by carefully sticking a piece of clear tape to the fingerprint, pulling it away and then sticking it to a white index card.
Be careful not to make a mess as you do this. The carbon will wash off, but it can be quite messy.
When you touch the glass, oils from your skin remain on the glass. Since your finger tip (and the rest of your skin) has ridges, not all the skin touches the glass. The tops of the ridges do touch the glass, leaving behind oils in the same pattern as your fingertip. The fingerprint powder sticks to this oil to make the fingerprint show up.
Have a wonder-filled week.
