manual
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PROJECT #8: Crystals
You will need: microscope
2 clean, blank slides
string
a drinking glass
very warm water (enough to almost fill the glass)
a spoon (to measure and stir with)
table salt
sugar
Take a piece of string about 3 inches (7.6 cm) long and tie it around the center
of an old pencil. Now take a small drinking glass and almost fill it with hot
water from the tap. Be careful not to burn yourself. Stir in a spoonful of salt
until it is well mixed and has all dissolved. Now add another spoonful and stir it
well. If all of the salt dissolves in the water, try to mix in a third spoonful.
Now place the pencil across the top of the glass so that the string is hanging
in the salt water. Place the glass somewhere safe where small children
cannot reach it. Do not move the glass around. Let it sit undisturbed for
a day and then examine the string. Leave it another day and examine the
string again.
You will see small white cubes growing on the string. These are salt crystals.
This crystal structure is salt’s basic shape.
Try the same experiment with a strong solution of sugar. Sugar also has a
crystal shape. Is it the same as a salt crystal? Can you tell them apart?
Look at some of the crystals you have grown under your microscope.
Sometimes the little cubes will join together in strange or beautiful shapes.
More Microscope Investigations
Always keep your eyes open to find other ways to use your microscope. Here
are two examples:
Toothbrushes—Compare the bristles of a new toothbrush to some from an
old, well-used one. Can you see why you should not use the same
toothbrush for a long time?
Printing—Compare printed material from different sources. Compare a
postage stamp with a piece of a newspaper or magazine picture. Can you
see the fine dots? How many different colors of dots are there? How can dots
of so few colors make all of the colors you see in a color magazine picture?
Salt Crystals
Sugar Crystals
Battery Installation and Instructions
1. Loosen the screws in the bottom cover of the microscope and remove the cover.
2. Install 2 AA batteries following the diagram inside the compartment.
• Do not mix old and new batteries.
• Non-rechargeable batteries are not to be recharged.
• Do not use rechargeable batteries.
• Do not mix different types of batteries: alkaline, standard (carbon zinc), or
rechargeable batteries.
• Only batteries of the same or equivalent type are to be used.
• Remove exhausted batteries from the unit.
• The supply terminals are not to be short-circuited.
• To prevent corrosion and possible damage to the product, it is recommended
to remove the batteries from the microscope if it will not be used for more than
two weeks.
3. Replace the cover and tighten the screws. Do not over-tighten.