Grade: all
Subject: Science

Teachers.Net Lesson Plans

#91. Kinetic Molecular Theory with Popcorn

Science, level: all
Posted by Cec Knight (
Peterborough County Board of Education, Peterborough, Canada
Materials Required: Popcorn, Hard Margarine, Hot Plate, 2 Beakers, (Optional: Hot Air Corn Popper, Salt , Paper Napkins)
Activity Time: 15 minutes
Concepts Taught: Heat , States of Matter, Kinetic Molecular Theory


The object of the game is to use popcorn kernels
as molecules and the margarine as the bonding forces
between them. Heating produces physical changes in the
popcorn-margarine mixture which are analogous to the
melting and boiling of matter.


- Melt 50 mL of margarine and add 100 mL of popcorn kernels
- Place the beaker in a refrigerator to harden
- Warm the beaker slightly in hot water to loosen the solid,
remove it from the beaker and keep it in the fridge


- Do whatever introduction you usually carry out to states of matter
- When you are finished, whip out the solid and explain that the
corn kernels are the molecules in a solid being held by the forces
which are represented by the margarine
- Review the properties of a solid using the chunk as an example
- Plunk the solid in a beaker on a hot plate and warm it until the
margarine melts
- Pour the "liquid" back and forth between the two beakers
- Talk about the properties of a liquid etc.
- Heat the "liquid" in a beaker over the hot plate until the
molecules begin to pop (watch splattering hot margarine but
don't cover the beaker)
- As the popcorn leaves the beaker, talk about the properties of
a gas
- The kids will want to eat the popcorn. As they write up what they
saw and explain it, make another batch in the hot air
popper and pass it around