What You Need: microscope, vial
of salicylic acid solution, thin pipette, colored plate, microscope slide.
The Amazing Crystallization Experiment
In nature it can take eons for crystals to form. How would you like to
watch them appear right before your very eyes?
CAUTION: Salicylic acid solution contains
rubbing alcohol. Don't swallow it or get it in your eyes. If it gets on
your skin or clothing, rinse it off.
What To Do: Set
the slide on the colored plate, which will make a good background for your
crystals. With the vial tightly capped, shake the solution for about 20
seconds. (Cap the vial when you're not using it so the alcohol doesn't evaporate.)
Using the thin pipette, drip a single tiny drop of solution onto the
middle of the slide. It should spread out to about an inch wide, then start
to dry from the outside edges. As it dries, place the microscope where you
can see some dry and some wet. From this point of view you can see an amazing
thing: the formation of crystals!
When the drop is completely dried, you can repeat the experiment by putting
another tiny drop right where you put the first drop.
Once your crystals have formed, you can get a better view of them by
using your microscope to look through the slide toward a light source behind
it. Keep the microscope light on, too.
ON THE AMAZING
Name some things that these crystals look like or remind you
| ||Sketch what the crystals look like through the microscope.|
WHAT GIVES CRYSTALS THEIR SHAPES?
||Everything is made up of molecules, but the molecules that form a crystal
are all the same as each other, and only fit together
in certain ways.
|This means when you put a bunch of these molecules together, they form a
||Let the pattern keep growing, and before you know it - PRESTO! - you've got a crystal.
©1997 by Stratton House
All the equipment for this experiment is included in Microscopic
A dash of color has been added to this page. The actual lessons are in
easily reproducible black, white and gray tones.
The above lesson is from the student worksheets. Additional notes and
questions are given in the parent guide.