Post on 23-Feb-2016
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Elephant ToothpasteBy: Ashley Morgan
Purpose
• The purpose of this lab was to mix two solutions together and form a
foam fountain.
• When performing this experiment, just by changing one material can
give you similar results.
Funnel
• A tube or pipe that is wide at the top and narrow at the bottom.
• It is used for guiding a liquid into a small opening.
Catalyst
• A catalyst is a substance that increases the rate of a chemical reaction without undergoing any permanent chemical change.
• In simpler words:– Helps a reaction happen faster
– Yeast – Potassium Iodide
Exothermic
• Releases heat and causes the termperature of the immeidate surroundings to rise.
Procedure #1• In a 16 oz bottle mix – 8 drops of food coloring– 1 tablespoon of dish soap (dawn)– ½ a cup of 3% hydrogen peroxide– 3 tablespoons of water– 1 packet of dry yeast (red star)– Watch reaction
Reaction!
Observations• Hydrogen peroxide molecules are very
unstable and naturally decompose into water & oxygen gas.
Hydrogen Peroxide -> Water -> Oxygen
2H2O2 2H2O O2
Observations• The yeast acted as a catalyst to remove the
oxygen from the hydrogen peroxide.– Since it did this very fast, it created lots of
bubbles!• This solution had a scent of freshly baked
homemade bread.• Each tiny foam bubble is filled with oxygen.
Observations• The food coloring changed the foam to a red-
yellow color.• The experiment created a reaction called an
exothermic reaction.– That means it not only created foam but also heat
as well.– It also created bubbles, which is a gas.
Question #1• Why is warm water best to use in this
experiment?– Warm water is best for yeast because yeast is a
living organism that likes to live in similar temperatures to humants
– Put the yeast in hot water and it dies– Put the yeast in cold water and it will be too cold
to reproduce.
What is actually happening?• Hydrogen peroide is water with one extra
oxygen. • When yeast is added, it acts as a catalyst to split
the hydrogen peroxide into water & oxygen.• Bubbles of oxygen are trapped in the soap,
which transforms into the foam fountain.• The product formed is just soap, water, and
oxygen.
Procedure #2• Mix in a 16 oz bottle– 40 ml of dish soap (dawn)
– 80ml of 3% hydrogen peroxide– 1 tablespoon of potassium iodide
– 8 drops of food coloring– 3 tablespoons of warm water
– Watch reaction
Reaction!
Observations• The overall equation for this reaction is:
• The dishwashing detergent captures the oxygen as bubbles.
• Food coloring changed the foam to a blue-green color.
2H2O2 2H2O (liquid) O2 (gas)
Observations
• This had a soapy scent of apples due to the dishwashing soap.
• The experiment created an exothermic reaction as well.
– The bottle was warm as well.– Bubbles were produced.
Similarities Differences• The both started
producing foam right away once the hydrogen peroxide was added.
• The bottles was warm.• Bubbles were produced.
• Scents– Apples– Bread
• Potassium Iodide experiment looked watery rather than bubbly
Conclusion• This experiment used hydrogen peroxide and potassium idodie/yeast mixed with dish soap and
water. • If you add all these together, the hydrogen peroxide’s decomposion is sped up the catalyst.
• Oxygen is given off and forms foam with the dish soap.
• The foam pushes up in the bottle and comes out the top looking like toothpaste.
Works Cited• http://www.using-hydrogen-peroxide.com/elephant-toothpaste.html
• http://chemistry.about.com/od/chemistrydemonstrations/a/elephanttooth.htm
• http://www.sciencebob.com/experiments/toothpaste.php
• http://www.wikihow.com/Make-Elephant-Toothpaste