Saturday, July 17, 2010

Mentos and Diet Coke

Supplies

2-liter of Diet Coke
6 mentos
paper rolled into tube (big enough for Mentos)
index card or card stock square

Concept: Diet Coke and mentos have an explosive reaction when they are combined. The Diet Coke starts to make holes or pit the candy rapidly. This causes a gaseous reaction producing a fountain, rather than dissolving the candy.

Procedure: Place 2-liter of Diet Coke on a flat surface (outside). Open the 2-liter and place the index card or card stock over the top. Place the rolled paper tube above the index card/card stock and drop in 6 mentos. Slowly pull out the index card/card stock square and allow the mentos to drop into the liter.

Extension: Try using various 2-liters of diet soda and non diet soda and compare results. Use different kinds of mentos (mint vs fruit) to document comparasion. Add more or less mentos and record how the results vary. Also, vary how quickly or slowly the mentos are dropped into the soda.

Application to the Real World: The show MythBuster's feautured an episode on this experiment concluding the caffeine, potassium benzoate, aspartame, and CO2 gas in the Diet Coke combined with the gelatin and gum arabic in the Mentos create the eruptive fountain. MythBusters also theorized the physical structure of the Mentos as a vital component in the eruptive effect due to nucleation.



Wednesday, July 14, 2010

Pop Rocks

Supplies

Pop Rocks candy (The World Market)
water
pipettes/medicine dropper (available at pharmacies)
Zip Loc bag
Dixie cup

Concept: At the candy factory for Pop Rocks the candy is processed with the gas carbon dioxide. When your saliva or water (for Zip Loc/Dixie cup) dissolves the sugar in the candy the gas is released and pops!

Procedure: Have students pinch Pop Rocks into a Ziploc bag, add some drops of water, seal bag and observe. Next have children conduct same experiment, but place Pop Rocks in a Dixie cup. Compare both experiments. Does, sealing the Ziploc bag cause a different reaction? Lastly, have your students place Pop Rocks and mouth and discover how saliva affects Pop Rocks.

Extension: Use different liquids to dissolve Pop Rocks (vinegar, peroxide, soda, milk) and compare reactions.

Application to the Real World: Carbon Dioxide is used in the food, oil and chemical industry. Carbon Dioxide creates the carbonation in Soda. Dry Ice is also frozen carbon dioxide.



Taste Sensations

Supplies

1 box of Baker's unsweetened chocolate
1 package of Sour Patch Kids
granualated sugar
salt
Dixie cups

Concept/Procedure: Have the students learn the four tast sensations- bitter, sour, sweet, and salty. Have them eat unsweetened chocolate for bitter, sour patch kids for sour, sugar for sweet, and salt for salty.

Extension: Have them do the sample again, but this time plug their nose to learn how sense of smell is closely connected to our sense of taste.

Application to the Real World: Our sense of taste provides us with the ability to detect flavor. Bitterness is the most sensitive of tastes, it is often viewed as unpleasant and sharp. Sourness it the taste detecting acidity. Sweetness is the taste detecting sugar and is often viewed as pleasureable. Salty is the taste detecting the presence of sodium. In the 2000s, the fifth taste sensation of savory has been advised by many authorities within this field. Savoriness is the taste sensation produced by amino acides. It is described as having a "rich" taste. The Chinese Five Elements Philosophy lists the five basic tastes as bitter, salty, sour, sweet and spicy. Japenese culture also adds a sixth taste to the basic five.



Monday, July 12, 2010

Silly Putty

Supplies

2 parts school glue
1 part liquid starch (Target sells a non aerosal spray starch; remove sprayer to pour)
Ziploc bag

Procedure: In a Ziploc bag pour 1/4 cup of glue and 1/8 cup of starch. Seal Ziploc bag and massage with fingers for a few minutes.

Alternate Recipe

1 Tbsp. school glue
1 tsp. water
1 Tbsp Borax and water mixture
Ziploc bag

Procedure: Place 1 Tbsp. school glue and 1 tsp. of water in a Ziploc bag. Keep down at bottom of bag. Take 1 cup of warm water and place in an empty plastic bottle. Add 1 Tbsp. of Borax to plastic bottle and shake until all is disolved (use funnel to help pouring water and Borax). Add 1 Tbsp. of Borax/water solution to the Ziploc bag and massage with fingers for a few minutes.

Concept: Creating a polymer. An elastomer, is any of the elastic (returns to original shape after being deformed) polymers, which have the elastic properties of natural rubber.

Extension: Have students find an old newspaper and transfer the picture of a cartoon from the comic section onto the putty and enjoy distorting the cartoon's imaging by stretching the silly putty.

Application to the Real World: Silly Putty (Dow Corning patent 3179) was origninally created in 1943. Initial intentions were for industrial use as a sythetic (artificially made) rubber. It was unusable for this purpose, since it was not as firm as rubber. However, in 1949 an unemployed advertising executive thought would be good to market as a toy. He packaged it in plastic eggs and it has been an American toy ever since. Because of this polymer's or elastomer's natural flexibility, it can be stretched and absorb mechanical energy in a similar manner as rubber.



Sunday, July 11, 2010

Flubber

Supplies

1 1/2 cups glue
4 Tbsp.Borax (laundry detergent aisle)
4 cups water

Concept: Creating a polymer. A polymer is a large molecule (macromolecule) composed of repeating structural units typically connected by covalent (The number of electron pairs an atom can share with other atoms) chemical bonds.

Procedure: Mix 2 cups of water and the glue in a bowl. In a empty plastic bottle use a funnel to add 2 cups of warm water and 4 Tbsp. of Borax. Shake bottle till Borax is dissolved. After it's dissolved, pour the Borax mixture a little at a time into the glue mixture and stir. You may not need all of the Borax mixture.

Extension: Make other sensory substance like mud, playdough, slime, and silly putty and test each substance for bounce, stretch, and stickiness. Have students document results.

Application to the Real World: Polymers play an essential role in our daily life's. They range from sythetic plastics(synthetic rubber, Bakelite, neoprene, nylon, PVC, polystyrene, polyethylene, polypropylene, polyacrylonitrile, PVB, silicone), to natural bipolymers like DNA, nucleic and proteins. Natural polymers include cellulose, natural rubber, amber, and shellac.





Wednesday, July 7, 2010

Worms

Supplies

Worms (in LA: Purfield's Pro Tackle 12512 Washington Blvd. Los Angeles, CA 90066
(310) 397-6171)

Concept: Hands on exploration with Earthworms. Use your sense of touch and sight to observe worm head and tail movement. Can you identify the head/tail? What is the small section on the worm that is different than the rest? Can they survive being split in two?

Extension: Compare these invertebrate (have no backbones) to other invertebrates.

Wormy Facts: Earthworms bodies are made up of ring-like segments called annuli. The segments are covered in setae(small bristles), which the worm uses to move and burrow. The worm's first segment contains its mouth. Earthworms breath through their skin. They also have a brain,5 hearts, and mouths. Worms eat a third of their body weight daily. The familiar-looking bulge seen near the first third of the earthworm’s body is clitellum. The clitellum is a series of segments that are swollen to form a saddlelike structure in the anterior portion of the oligochaete. The function of the clitellum is mucous secretion during copulation and cocoon formation after copulation. Lastly, contrary, to the common myth; if split in two, two will not grow.

Application to Real World: While burrowing worms consume soil and extract nutrients from decomposing organic matter (leaves and roots). Earthworms are crucial to soil health since they carry nutrients and minerals from below to the surface through their waste and their tunnels aerate (air/ventilate) the ground. Earthworms are a source of food for many animals (birds/rats/toads). They also are frequently used in residential composting and as bait in commercial and recreational fishing.





Tuesday, July 6, 2010

Oobleck

Supplies

newspaper
measuring cups
1 c. of dry cornstarch
large bowl
green food coloring
1/2-1 c. of water

Procedure: Cover you table or counter with newspaper (if possible complete experiment outside). Put the cornstarch into the bowl or pan. Add a few drops of food coloring. Add the water slowly, while mixing. Continue to add water until all of the oobleck feels like a liquid when your mixing it. You will have perfect consistency when you can tap on the surface of the oobleck and it feels like a solid. If too powdery, add more water. If too wet, add more cornstarch. Play and experiment. What happens when you squeeze a handful?

Extension: Make other sensory experiments (flubber, play dough, silly putty, mud, handmade sand).

Application to Real World: Discuss matter and various solids, liquids, and gases we have/use in our daily life's.




Volcanoes

Supplies:
vinegar
baking soda
red food coloring
liquid dish soap
play dough
paper plates
Dixie cups
measuring utensils

Play Dough Recipe
2 c. flour
1 c. salt
1 c. colored water
1 tsp. alum (optional to preserve)

Alternate Play Dough Recipe
1 c. flour
1/2 c. salt
1 Tbsp. cream of tartar
1 c. water
1 Tpsp oil
Optional: add vanilla or peppermint extract before cooking. Smell is our strongest link to memory.
(mix and cook over skillet on low/medium heat for 3-5 minutes)

Concept: Vinegar causes the baking soda to bubble and turn into a gas (carbon dioxide). The dish soap slows down the chemical reaction to form the lava.

Procedure: Place Dixie cup on center of paper plate. Use play dough to form base of volcano. Have student measure 1 Tbs. of baking soda. Place into Dixie cup inside crater of volcano. Squirt one squirt of liquid soap into crater of volcano. Take volcanoes outside for eruption time. Let students pour one Dixie cup full of vinegar into volcano (can be repeated by adding more vinegar).

Extension: Experiment with different materials to form volcano. Add more or less dish soap, baking soda, vinegar and observe.

Application to Real World: Why do volcanoes erupt? A volcano is a vent through which molten rock escapes to the earth's surface. Unlike other mountains, which are pushed up from below, volcanoes are built by surface accumulation of their eruptive products - layers of lava, ashflows, and ash. When pressure from gases within the molten rock becomes too great, an eruption occurs. Volcanic hazards include gases, lava and pyroclastic flows, landslides, earthquakes, and explosive eruptions.



Thursday, July 1, 2010

Balloon Blow Up

Supplies

1. empty plastic bottle filled half way with vinegar
2. 1 Tbs. of baking soda
3. balloon(s)

Procedure: Place balloon on funnel. Have students measure and pour 1 Tbs. of baking soda into the funnel. Have students gently remove balloon from funnel. Set balloon with baking soda aside. Use funnel in bottle and let student pour about 1/2 the bottle with vinegar. Use marker to mark measurement on bottle. Carefully place balloon over mouth of bottle, make sure the baking soda does not pour into vinegar, yet. On the count of 3, have students lift balloons and let baking soda fall into the bottle.

Concept: Chemical Reactions- Carbon Dioxide gas. Tip the bottle upside down and let all the ingredients fill the balloon. Touch the bottom of balloon to feel how cold these chemicals get.

Extension: Use yeast to replace baking soda and hydrogen peroxide to replace vinegar to make a different gas (oxygen). This experiment makes heat. It does not produce as much gas, but is much warmer.

Application to Real World: Why do helium balloons rise? Helium rises because it is less dense than the air. If it is less dense, then it will rise above the air until it meets a gas lighter than it. There are other gases lighter than air. You should experiment with other gases inside balloons.