Sloppy, Drippy, Wonderful Science

Quick electrons zip

zoom and spin madly around

the lonely center
-- An Atomic Haiku by Scarlett

Up, Down, Charmed, Lucky

Who are these strange particles?

Quarks, atom's centers
-- Particle Haiku by Caddie

Matter, what could it be? Listen and I shall tell thee. Matter is made up of particles -- and don't forget the energy! -- Matter II by Caddie

Chers Amis,

If it is drippy, sloppy and school, it must be time for Adventures in Science! our weekly science experiment club. This term we have been focusing on chemistry, elements, atoms, the periodic table, and most recently, charges. We have adopted elements, built models of atoms, and even written poetryabout the humble building blocks of our universe. (Yes, Caddie knows that the center of an atom is the nucleus, she insisted that since protons and neutrons are formed by quarks they are the true centers. Argh!)

Last week's experiment sought to answer the question, "Are molecules affected by charges?" by using balloons, water, paper cups, a plastic pen, bubbles, a silk cloth and our heads - in more ways than one ;-) We based the experiments on several in Adventures With Atoms and Molecules: Chemistry Experiments for Young People and this activity at the Atom's Family. Vocabulary included: polar and nonpolar molecules, neutral, attract, repel and electrostatic charge.

First, the young scientists rubbed a balloon on their hair and recorded their observations. Did it produce a charge? How did the charge affect the hair? Did it change the balloon? How? Even Pippin recorded his observations in graphic detail. (Don't you love the eyes!) Next came a cloud of bubbles. As the TA's (moms) filled the room with bubbles, they had to determine if the bubbles reacted differently to the balloon depending on whether or not the side of the balloon approaching the test bubble was "charged". This involved more rubbing. Try it. There is a difference. Here is a good explanation of the scientific reasons the "charged" or rubbed side attracted the bubbles. In short, when the balloon is rubbed against your hair "you rub electrons onto the balloon" or impart a negative charge to the balloon. The water molecules in the bubbles are polar - having two ends like a magnet. The negative balloon attracts the positive polar molecules of the bubble. We also found that the unrubbed side of the balloon repelled or pushed the bubbles away!

In the second experiment, we poked a hole in the bottom of a paper cup, filled the cup with water and covered the hole with a finger. The scientists rubbed a plastic pen with silk to produce a charge. As the water stream was released, each girl (Pippin had evaporated) brought the pen near the stream of water and recorded her observations. Could a charged pen affect the water stream? If so how? (We also tried this using a very fine stream of water from the tap and it produced more dramatic results. ) Here is a good scientific explanation. Try this with oil. Does it have the same effect? Why not? What does it mean? (Hint: oil is nonpolar :-) .

Tomorrow is science day again and we are going to continue talking about polarity and how it produces surface tension, discuss whether or not similar molecules attract each other and if so why. Soap is involved so maybe it won't be too messy :-) For a interesting science this week, read try Q is for Quark: A Science Alphabet Book by David M. Schwartz.

-- Marjorie

PS - Next week is National Chemistry Week - To quote Ms. Frizzle, "Take chances, make mistakes, and get messy!"