STUDENT CHALLENGE
The goal of this project is to help students visualize chemical reactions and density.
Students will observe what happens when materials have different densities and what
can occur when you mix two reactive substances together.
BUILDING
MATERIALS
ENGINEERING DICIPLINES APPLIED
Chemical Engineering/ General Chemistry
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LEARNING OBJECTIVES
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Basic understanding of chemistry and chemical reactions
Basic understanding of density
PROCEDURE
1. Using the funnel, fill 1/3 of the bottle with water.
2. Using the funnel, fill the rest of the bottle with oil, leaving some space at the top
to avoid overflow.
3. Add a few drops of food coloring. Observe how the food coloring falls through
the oil and mixes with the water.
4. Break off a piece of an effervescent tablet and drop it into the bottle. Observe
the reaction. Warning: Do not replace bottle cap while reaction is occurring
because it will allow pressure to build up in the bottle.
DISCUSSION QUESTIONS
1. Why didn’t the oil and water mix?
2. Why doesn’t the food coloring mix with the oil?
3. What happened when the tablet was dropped in? Why did this happen?
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1 one liter clear
bottle
1 Funnel (if using
narrow necked
bottle)
Water
Oil (mineral or
vegetable)
Food Coloring
Effervescent
tablets (such as
Alka-Seltzer)