Coke and mentos

Drop mentos into coke to produce a fountain of foam.
Science content
Chemistry: States of Matter, Properties of Materials (K-7)
Chemistry: Physical Changes, Solutions, Mixtures and Separating (2, 4, 5, 6)
Lessons activity is in
  • diet coke, 2l bottle
  • mentos, one packet of mint (the fruit flavour ones are coated and don't work)

Open the bottle of diet coke and place in an open space.
Move the students back.
Dump the mentos in the coke as fast as possible (can use a paper funnel).

A giant fountain of foam is produced.

The mentos have a very bumpy surface that provides a place for bubbles of carbon dioxide to come out of solution. It does so rapidly, generating a mass of bubbles which stay around long enough to form a foam that geysers out of the bottle.

Grades taught
Gr K
Gr 1
Gr 3
Gr 4
Gr 5
Teaching site
Gordon Elementary Science Club
ingridscience afterschool
JEMZ+ After school science