Styrofoam Cups Vanish Into Thin Air Activity
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ward
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science
Recommended Grade Level(s):
Appropriate for: Grades 4+
Time Requirements:
Activity Time: 20–30 minutes
Teaching Topics & Concepts:
• Covers concepts of chemical reaction, bonding and molecules, and the law of conservation of mass.
Materials:
• Styrofoam cup
• Acetone (Pure acetone works better than nail polish remover.)
• Glass bowl or aluminum pie plate
• Chopsticks or a spoon
Background
All mass is conserved and never destroyed or created. We use scientific methods to demonstrate the way different materials are
put together, act under different conditions, and go through changes. Dissolving and melting are examples of processes where
substances go through change. When something dissolves, an additional substance (a solvent) is needed. Dissolving can involve
chemical changes (for example, antacid tablets or salt mixing with water or metal dissolving in acid). Melting and freezing of
materials are dependent on their temperature. When something melts, the liquid is the same substance as the solid. Students can
conduct this activity to observe dissolving and learn how to distinguish it from melting.
Safety
• Adult supervision is required.
• Acetone should be properly disposed of when done, as well as any paper towls or items used during the
experiment. It is very flammable and should be handled only by an adult.
• Wear safety gloves and safety goggles.
• Follow the manufacturer's warnings on the container of acetone. The solvent is very flammable and can be
harmful if inhaled.
• Perform the demonstration in a well-ventilated room, outdoors or in a hood (keep a safe distance to avoid
inhaling the vapors).
• Keep acetone bottle capped when not in use, and do not do this demonstration in conjunction with any
open flames.
!