Friday, August 7, 2015

Adventures in Chemistry

Glow fast, glow slow reaction

Colors on the move!
Monday was all about reactions!  We kicked off chemistry week with a few cool experiments to get us feeling like like real chemists.  We created an iodine clock reaction, titled as such because it's a reaction that takes a specific amount of time depending on the concentration.  You could set your watch by this reaction!  Our Glow Slow, Glow Fast activity explained how reactions occur faster in hot environment rather than cold because hot environments have more energy.

Our chemistry rocket activity explained the reaction between acids and bases.  By releasing carbon dioxide, our reaction was able to propel our rocket into the air!
Explaining our experiment
Colors on the move is a simple experiment you can do at home!  The fats in milk will be repelled by dish soap, so by adding dye to milk and placing a q-tip in the center of the drop, we were able to send the colors swirling around our milk.

Set up!

Tuesday campers learned more about chemical versus physical reactions.  Our cloudy globs experimented showed the reaction between ammonia and alum, changing our clear solutions to clouds in a bottle.  Our iodine and vitamin C experiment was a chemical reaction that showed how different chemical can change color in the presence of others.

Visiting from the Hands On Museum

Recording our data

The Hands On Museum made a visit and taught us about different reactions as well.  Ask your camper about their visit!

Floating "m"s

Wednesday, campers learned about the chemistry of candy!  Our mysterious floating "m"'s experiment got us thinking about different kinds of stamps and dyes in the food we eat.  Our candy chromatography made us question if black dye really is black! Our Mentos geyser was a physical reaction between diet coke and Mentos.


Blast Off

The reaction release the carbon dioxide dissolved in the soda to create an enormous geyser!  Our incredible growing gummy bears are one of the few candies that do not dissolve in water.  The gelatin based gummy bears actually expand as they absorb water!

Growing gummies

Making our bouncy balls!
Thursday's camp was all about polymers!  Polymers are long chains of molecules made up of individual units called monomers. Polymers can be sticky or stretchy because these molecule chains become tangled and difficult to separate.  We performed some tests on different household items to determine what is or isn't a polymer.  Many polymers can also absorb large quantities of liquid!  We tested different kinds of water absorbing polymers against one another to determine which worked best.  We also made magnetic slime!  By adding iron filing to a tangled network of polymers, we were able to move our slime using only a magnet.  Our favorite activity of morning was making our own bouncy balls.
Bouncy balls, too, are made of polymers which gives them their great bouncy abilities!

Elephant toothpaste
Hot ice!
Friday, we learned about exothermic and endothermic reaction.  An exothermic reaction is a one that generates heat as a product or byproduct.  An endothermic reaction absorbs heat.  Our first experiment was our exothermic reaction called elephant toothpaste.  This experiment used yeast to catalyze (make faster) the the release of oxygen from hydrogen peroxide.  A squirt of dish soap become a volcano of foam when encountering this mixture.  Oxygen is produced and the separation of the atoms produces heat.  Another exothermic reaction we undertook was our homemade hand warmer!  By combining the following, the chemical reaction between the iron, calcium chloride salt, air, and water (locked inside jelly crystal.) not only produces iron oxide, but also heat.  Hot ice is another reaction that produces heat.  By supersaturating water with sodium acetate, you can turn the solution back into a solid instantly by adding just a few crystals.  This gives the appearance of instant ice while the process of crystallization gives off heat.  Our endothermic reaction for the day combined citric acid and baking soda.  In the presence of water, citric acid and sodium bicarbonate (aka baking soda) react to form sodium citrate, water, and carbon dioxide.  This process actually uses heat rather than produces heat.

Future chemists

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