Crystals as we saw in the last Project have regular shapes. Not everything we look at as a crystal is really a crystal like sugar. Can we grow sugar crystals?
The sugar crystals are called rock candy. If you used clean string and jars, you can eat it.
Question: How do different crystals grow large?
Piece of charcoal
Growing sugar crystals:
Pour 1c water into a medium sized saucepan
Add 2 1/2c sugar
Heat as you stir to dissolve the sugar
Stop stirring when the sugar dissolves
Heat the solution to boiling [Be careful as it will quickly foam up and out of the pan when it boils.]
Cut a length of string long enough to tie to a pencil and reach to the bottom of the jar
Tie the string to the pencil
Tie a little weight to the other end [I used a tiny nail.]
Wet the string
Pour the sugar solution into the jar almost to the top
Dangle the string in the solution so it doesn’t quite touch the bottom of the jar
Set the jar aside to let the sugar crystals form [This can take a week.}
Growing salt crystals:
Put a layer of salt 1cm deep on the bottom of the jar
Add water so it is 1cm over the salt
Set the piece of charcoal on the salt layer
Set the jar aside for the salt crystals to form [This can take a week.]
Describe the sugar solution you pour into the jar
Describe the sugar crystals each day for a week
Describe what happens in the jar of salt and charcoal every day for a week
Why do you put a weight on the end of the string?
Are the sugar crystals true crystals? Why do you think this?
In the last Project salt formed cubes as crystals. Does it form cubes on the charcoal?
What is happening to the salt crystals on the charcoal?
What I Found Out:
Hot water dissolves a lot of sugar. The solution gets thick. I could see swirls as I stirred.
When I stopped stirring, the solution became very clear but slightly brown in color. It suddenly foamed up and out of the pan.
Plain string floats on the sugar solution. I used a tiny nail to add weight to the string so it dangled down into the solution in my two jars. The solution was too much for one jar.
In a few hours clear sugar crystals formed across the tops of my two jars. These had some hard bubbles or foam on top.
By the next day these top layers were thick. One jar had crystals forming on the bottom. No crystals were forming on the strings.
On the third day some crystals were forming on the string and nail in one jar and the string in the other one.
Nothing seemed to happen on the first day in the jar with the salt and charcoal. The charcoal was very wet and shiny.
By the second day I could see little white spots on the charcoal. These began to look like spider webs on the charcoal. Then little mounds started building up on the charcoal.
These salt crystals looked entirely different from last Project. They look like stalagmites in a cave. It looks like the salt water pulls up over the charcoal and the water evaporates leaving a mound of salt behind.
When you set up the charcoal, put food coloring on the charcoal. You can put several drops of different colors in different places or several drops of one color in different places. How does this change the salt crystals?
Look up the Devil’s Golf Course in Death Valley. This is the charcoal set up by nature on a gigantic scale.