Hello Arcola!!!

1. By: Loudoun SciencePals Bring out the science in you!!! Hello Arcola!!!

2. About us • Minna Kuriakose and Madie Luberecki • Science is our passion • Do not hesitate to ask us questions!

3. Surface Tension • What is it? Water molecules have a slight positive charge on the hydrogen and a slight negative on the oxygen. The water molecules are attracted to each other. This makes water a "polar" liquid.

4. Surface Tension • The molecules on the surface of the water attract to each other since there is no other water molecules above them. This attraction creates a “skin” which can hold light things. ML fusedglass.org

5. Paper Clip Magic and Scared Pepper! – Surface Tension Examples of surface tension ML

6. Paper clip floating? • Hypothesize – Do you think that the paper clip will float or sink? • The paper clip sank!!! • But can we make it float???

7. Materials to make a Paper Clip Float • Paper clip • Bucket or container • Tissue paper/toilet paper • water

8. Procedure • Fill the bucket will about 3 inches of water. We already know that the paper clip sinks. • Put the paper clip on to the tissue paper and carefully place the tissue paper with the paper clip on top of it into the water • Wait for the tissue paper to sink to the bottom and observe the paper clip

9. What happened? • SURFACE TENSION!!! The water molecules at the surface were attracted to each other and created a “skin” that we talked about in the earlier slide. This skin was strong enough to hold the paper clip.ML

10. Scared Pepper – Surface tension • Pepper seems to be really scared of dish soap today. • Lets see what happens to pepper in the water when we drop in the dish soap!

11. Materials • Pepper • Small bowl • Water • Dish soap • Tooth pick • Small plate

12. Procedure • Fill the bowl 3/4ths with water and sprinkle some pepper on it. • While waiting for the water to settle down, pour some dish soap into a small plate. • Use the toothpick to take some dish soap out of the plate and let the toothpick touch at the center of the pepper in the bowl • Observe what happens to the pepper

13. Scared Pepper? Why • Why is the pepper “scared” of the dish soap The pepper used the surface tension of the water to float on it. The dish soap interrupted the surface tension right in the center of the bowl, so the pepper floated away from it to find the water that still had surface tension.

14. Elephants shampoo! www.sciencebob.com

15. Elephants Shampoo • Hypothesize – What will happen if hydrogen peroxide is decomposed?ML

16. Materials • Hydrogen peroxide • Gloves • One tablespoon dry yeast • 3 Tablespoons of warm water • Liquid dish washing soap • Food coloring • Small cup • 16 ounce plastic bottle

17. Procedure • In the plastic bottle, pour in a small amount of hydrogen peroxide (BE CAREFUL, GET ADULT HELP!!!) • Pour in small amount of dish soap in to the bottle and carefully mix the dish soap with the hydrogen peroxide. Put the bottle in a tray or a washable surface to avoid mess. • In the small cup, put the 3 table spoons of warm water and the one tablespoon of yeast. Mix the two together • Pour the yeast mixture into the bottle and observe the “elephant’s toothpaste” (IT IS NOT REAL TOOTHPASTE, DO NOT PUT IT IN YOUR MOUTH!!!) • Observe what happens to the mixture in the bottle

18. What happened? • Decomposition is when one substance is split into two other substances.ML • The foam had tiny foam bubbles that were filled with oxygen. The yeast acted as a catalyst (a helper) to remove the oxygen from the hydrogen peroxide. Since it did this very fast, it created lots and lots of bubbles. And as a result, we got the foam!!!

19. Any Questions?

20. Thanks for Watching!