Transcript Intermolecular Polarity

Let’s make a Lava Lamp
By: Loudoun Science Pals
About Loudoun Science Buddies
Mercer Middle School Club
Team members: Minna Kuriakose and Madeline
Luberecki
Science is our passion
Experiment
Today’s experiment is a fun one. Today we will
make a homemade lava lamp.
Materials
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Clear 16 ounce plastic water bottle
Vegetable oil
Water
Food coloring
Alka-Seltzer tablets
Sharpie
http://www.wired.com/geekdad/2007/07/alka-seltzer-ta/
Procedure
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Make a mark with the sharpie at about ¾ of the bottle
Fill the bottle with an inch of water
Pour vegetable oil into the bottle till you reach the mark.
Wait for the vegetable oil and the water to separate in the
bottle
Pour 10 drops of food coloring, more or less depending on
what you like
Wait for the food coloring to fall and mix with the water.
Once the food coloring is well mixed, take an Alka-Seltzer and
break it in half.
Drop the Alka-Seltzer into the bottle and watch the lava lamp
come alive.
For more special effects, place the bottle on top of a flashlight
in a dark room and drop the Alka-Seltzer
What’s the Science behind this?
Density and
Intermolecular Polarity
What is density?
• relative “compactness” of objects with a constant
volume
Density of water: 1,000 kg/m³
Density of Olive oil: 918 kg/m3
How does it work?
• Since the oil is less dense than the water, the oil
sits on top of the water. When it is dropped into
the oil, the food coloring falls to the bottom with
the water. The food coloring (water based) and
the water do bond together, so they mix well.
Why don’t oil and water mix?
(Intermolecular Polarity)
• Water molecules have a slight positive charge on
the hydrogen and a slight negative on the
oxygen. This makes water a "polar" liquid.
Why don’t oil and water mix?
• Oil particles are made of chains of carbon atoms
bonded to hydrogen. The elements and structure
of oils make them non-polar.
Because water molecules are polar and oil
particles are non-polar, the water and the oil don’t
mix.
What next?
• When the Alka-Seltzer is dropped it reacts with
the water. It creates gas bubbles which rise to
the top of the bottle carrying the water with it.
This is why you see the bubbles.
Reflection Questions
• Does the temperature of the water affect the
reaction?
2. Does the size of the bottle affect how many
blobs are produced?
3. Does the effect still work if the cap is put on
the bottle?
4. Does the size of the tablet pieces affect the
number of blobs created?
Citation
• Any picture that is not cited has come from clipart
• http://www.wired.com/geekdad/2007/07/alkaseltzer-ta
• http://chemstine.com/Lessons-andHomework7.php
• http://www.ujnews.com/happy-birthday-lavalamps/
• http://www.spencersonline.com/product/lavalamp-with-purple-lava-yellow-liquid-and-silverbase/
• http://serc.carleton.edu/mathyouneed/density/ind
ex.html