Catalyst - Halloween 2010FUN GRAPH FRIDAY!!!! • What is this graph saying about Halloween weather and costumes?
HAPPY HALLOWEEN! Today we will be learning about some spooky science things… Do you dare????
Today’s Agenda Chemistry of Glowsticks Lightning In Your Mouth! Watch Out! Dry Ice is Made for Mad Scientists! Slime! Ooey Gooey! (Extra Reward for 4th period)
THE CHEMISTRY OFGLOWSTICKS • Glow sticks were invented about 25 years ago. • The chemistry behind glow sticks is actually pretty simple.
THE CHEMISTRY OFGLOWSTICKS • Light is a form of energy which can be emitted (or given off) through a variety of processes. • These processes are called…CHEMILUMINESCENCE
THE CHEMISTRY OFGLOWSTICKS • The glow stick itself is like a portable chemistry reaction. • The chemical reaction is set off by mixing chemical compounds. • The reaction excites atoms, which then emit light.
THE CHEMISTRY OFGLOWSTICKS • What is reacting? • HYDROGEN PEROXIDE • PHENYL OXALATE ESTER • FLUORESCENT DYE
WHAT HAPPENS IN AGLOWSTICK? • A glow stick is a plastic tube with a glass vile inside it • Tube bends, vial breaks, chemicals mix and react • Chemiluminescence: energy released in the form of light
THE CHEMISTRY OFGLOWSTICKS • Chemists can make this in the lab! • The chemicals are actually toxic, so it is better to just buy glow sticks rather than make them yourself.
LIGHTNING IN YOUR MOUTH • After the lights are turned out, wait until your eyes adjust to the dark. • Bite down on a the wintergreen candy while looking in a mirror.
LIGHTNING IN YOUR MOUTH • You just made light with friction. The scientific name for this process is triboluminescence • When you crush sugar crystals, the stress in the crystal creates electric fields. Like the electric fields in a lightning storm, these electric fields can rip the outer electrons from molecules.
LIGHTNING IN YOUR MOUTH • When the molecules recombine with their electrons, they emit light. In addition to blue and violet light, the crunched crystals produce ultraviolet light, which you can’t see. • Wintergreen oil converts ultraviolet light into visible blue light, making the light you can see brighter.
DRY ICE = MAD SCIENTIST! • Is it smoking? • Are the liquids in the beakers boiling? • Dry ice is SOLID carbon dioxide, CO2 • It SUBLIMES, which means it changes from a solid straight to a gas!
DRY ICE = MAD SCIENTIST! • Have fun making your own Mad Scientist potions!
SLIME = OOEY GOOEY! • Borax: sodium tetraborate • + Water: H2O • + Elmer’s Glue: secret ingredients • + Food Coloring: Propylparabenand dyes • = OOEY GOOEY SLIME!!!!!!!!!!
SLIME = OOEY GOOEY! • Follow the directions for making slime carefully! • Please use only the allotted amount of glue as others will be making this also today! • If you want to keep your slime, you may put it in a plastic baggie • If you don’t want to keep your slime, you can give it away or throw it away
SLIME = OOEY GOOEY! • Grab ONE bottle of glue PER group. • Put 2 spoonfuls of Borax into a beaker and stir well. • Fill the beaker with water. • Add food coloring if you like. • Squeeze glue into Borax solution. • Find your SLIME!!!!!
EXIT QUESTION • In your own words, describe how glow sticks work. • What was your favorite thing about Spooky Science Day?
You are in a cookie factory, and need to make a huge batch ofchocolate chip cookies. The recipe calls for exactly 4 cups of sugar.Problem is that you have two buckets. One is 5 cups, the other is 3cups. Using these buckets, can you measure exactly 4 cups of sugar? How?