Students will
learn that fluoride helps protect teeth against decay.
Students will
make observations of chemical reactions.
Materials:
Fluoride solution
(available from your dentist, a dental supply company, or
some pharmacies)
Vinegar
2 hard boiled
eggs
3 clear containers
Science journals
Pencils
Instructions:
1.
Have the students
take out their science journals to prepare for the experiment.
2.
Place one egg
into a container and pour in enough fluoride solution to cover
it.
3.
Let the egg
soak for five minutes. Remove the egg.
4.
Pour four inches
of vinegar into the remaining two containers.
5.
Place the treated
egg into one container of vinegar, and the untreated egg into
the other.
6.
Ask the students
to carefully observe the reaction in either container. The
bubbling in the non-treated egg is a chemical reaction of
the acid in the vinegar with the calcium of the eggshell.
The acid is dissolving the untreated eggshell. The fluoride
treatment protects the one egg's shell from the acid, while
the acid attacks the untreated egg's shell. Our teeth need
to be protected from the acids in our mouths with fluoride,
too. In order to keep our teeth healthy, we need to keep them
clean by brushing and flossing, use fluoridated toothpaste,
eat healthy foods, and visit the dentist twice a year.