Growing crystals

Grow your own crystals at home!

You will need:
• Measuring cup (1/2 or 1 cup size)
• Glass mixing bowl (one that holds at least 2 cups)
• Spoon or other stirrer
• Beaker (we used the bottom of a plastic Snapple bottle - you could use a glass bowl or bottom of any plastic soda bottle)
• Rock or mineral from your neighborhood (we used a piece of granite - choose a rock that doesn't fall apart when you rub it)
• 1 cup of boiling water
• 1/2 cup of copper sulfate powder (you can buy it on eBay - you can use salt, sugar or other substances, but do a Google search for instructions or check here for ideas)

Safety note: Copper sulfate is a mild skin irritant. Work carefully with a parent's supervision, or better yet, wear regular rubber gloves when handling the powder and copper sulfate solution. Never taste the powder or drink the solution.

What to do: Pour 1/2 cup of copper sulfate powder in your cup (don't over fill the cup!). Then pour 1 cup of boiling water in with the powder (may need a PARENT'S or other grown-up's help). After that grab your spoon or other stirrer and mix well so there is no powder left in the glass. Then get your other cup that will hold your rock. Place your rock in the middle of your cup so the edges of the rock are not touching the cup or glass. Next pour the copper sulfate solution in with the rock until the rock is completely covered. Finally, move your glass with the rock and copper sulfate solution to a place where it won't get disturbed. Let the solution evaporate and the crystals grow for TWO WEEKS or more.  

Measuring 1/2 cup of copper sulfate powder

Pouring in 1 cup of boiling water

Mix thoroughly until all the powder has dissolved

Pour copper sulfate solution over your rock in the "beaker"

Several blue copper sulfate crystals after two weeks of growth

What happens: You might see blue crystals start to form on your rock, in the bottom of the cup, and around the rim of the cup in the next day or over the first few days. Do not disturb them if you want them to grow big and all over the rock.

Why: The blue crystals grow on the rough edges of the rock because you've created a saturated solution of copper sulfate and as the water evaporates, the copper sulfate solution becomes more concentrated and copper sulfate crystals precipitate out of the solution. The 1:2 solution of copper sulfate powder to boiling water is almost perfectly saturated at that ratio (the hotter the water, the more powder you'll be able to dissolve).

What happened when CKS tried it: In the picture above, it's showing the crystals in the cup after about two weeks. The crystals mostly cover the rock for CKS and they've gotten pretty big! We tried weaker solutions of copper sulfate and they did not work very well - fewer crystals grew and the crystals never grew very big.

CKS rating: 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 - THIS IS THE BEST ONE YET!YAHOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

Balloon Blow-UP

Blow up a balloon without using your lips!

You will need:
baking powder
vinegar
funnel (clean and dry)
small-mouthed bottle, large test tube or beaker
regular-sized balloon

What to do: Pour about 1/2 to 1 inch of vinegar into the bottle. Turn the funnel upside down on a table and stretch the mouth of a balloon over the small end of the funnel. Fill the about half of the balloon with baking powder. Remove the balloon from the funnel, then while letting the full end of the balloon dangle over the side of your bottle, stretch the mouth of the balloon over the mouth of the bottle. When you're ready for some excitement, tip the baking soda out of the balloon and into the vinegar. Continue to hold the balloon onto the bottle so it doesn't fly off...

What happens: When the baking soda mixes with the vinegar, bubbles form and the balloon starts to inflate.

Why: There is a chemical reaction between the baking soda and the vinegar that forms carbon dioxide gas (the gas in the bubbles and the gas that fills the balloon). The gas continues to form as long as there are enough reactants (the baking soda and vinegar) for the reaction to continue.

What happened when CKS tried it: It starts to form bubbles and it hissed. The balloon gets bigger until the bubbles start to go down. We used water balloons and they were too small - we couldn't fill them with very much baking soda and there was enough gas to fill a bigger balloon so next time we'll use a regular balloon.

CKS also tried testing for the carbon dioxide gas: Add the baking soda to the vinegar in a clear glass (so that you can see what's happening inside the glass). Have a parent light a candle and see that it burns bright in the air. Slowly lower the candle into the glass to see what happens.

Carbon dioxide is heavier than air and sits at the bottom of the glass near where the vinegar and baking soda reacted to form those carbon dioxide bubbles. When the flame of the candle enters the carbon dioxide layer at the bottom of the glass - poof! - it goes out with no oxygen there to feed the flame.

CKS rating: 4 stars - better than toys!

Tasting Through Your Nose - Experiment #102

"The smell of a food is as important as its taste! In fact, its smell actually influences how it tastes! If you doubt it, try this experiment.

You will need: 
Small peeled potato
2 spoons
Small grated apple
Grater


What to do: Grate part of a peeled potato and put it on a spoon. Grate an equal amount of a peeled apple and put it on a second spoon. Close your eyes and mix up the spoons so that you're not sure which is which. Hold your nose and taste each of the foods.

 

 

Why: The nose shares the airway (the pharynx) with the mouth. Therefore, we smell and taste food at the same time. Only salty, sweet, bitter and sour are pure tastes. Other "tastes" are combinations of taste and odor. Without the help of your nose, you may not be able to tell what you are eating."

What happened when CKS tried it: The potato tasted like both, but the apple tasted crunchy and sweet. I tried tasting chunks of potato and apple too. I guessed everything right - I knew which one was potato and which one was apple. They looked different so use a blindfold too. I guess I'm a good taster!

CKS rating: 4 stars - so fun you should try it a hundred times!

Blow the Book Away - Experiment #76

"Move a book back and forth by blowing on it? Try it!

You will need:
Two long pieces of string or rope
Book
Wooden clothes hanger

What to do: Loop two pieces of string around the book and knot them. Then tie the loose ends of the strings to the rod of the wooden hanger so the book swings freely. Blow on the book. Continue blowing on it every time it swings back toward you.

What happens: Even gentle blowing seems to make the book swing vigorously.

Why: It is not only a question of force, but also one of timing. Although you may not be blowing very hard, regular blowing at the right moment sends the book flying." 

What happened when CKS tried it: It only works when you blow hard and fast. It was a little bit scary to use a big book because it might fall on the floor and make a big noise or land on your toes. When you try it, make sure to use a light, small book.

CKS rating: 3 stars - As good as an ice cream cone.

The Great Coin Blowing Demonstration - Experiment #164

"Do you know anyone who can blow hard enough to blow a small coin all the way across the mouth of a glass? Of course you do. You can!

You will need: 
Drinking glass
Small coin

What to do: Put the drinking glass on a table. Balance the coin on the rim of the class like this: Blow sharply on the edge of the coin....Now, balance the coin on the rim of the glass again. This time you are going to blow the coin all the way across the open mouth of the glass so it lands on the table on the opposite side of the glass. Impossible? No, you can do it! Blow hard. The coin will probably fall into the glass the first few times you try. You must blow right at the edge of the coin....Don't place your lips too close to the coin. Stay back several inches and blow straight at the coin's edge. Blow hard and fast.

 

 

What happens: The first time you tried it, the coin fell off the rim of the glass. It may have fallen into the glass or onto the table. But that's what you expected, wasn't it? When you lined up everything correctly, the coin sailed across the glass and hit the opposite rim, but the force of the rapidly moving air kept it going.

Why: The coin is light enough for the moving air from your lungs to set it in motion. It had very little friction to overcome, because it was balanced delicately on the rim of the glass. It's all a matter of directing the coin in the path it needs to take. Air speed does the rest."

What happened when CKS tried it? When CKS tried it, she never got the coin across. She kept trying and trying and trying, but it never worked. The coin kept falling into the glass. Mad Dad Scientist was able to get the penny across the glass two times. But wait! For this to work, you have to line your mouth up with the edge of the coin.

CKS rating: 0 stars - Like cleaning my bedroom....thbbppppt!

Eggs-tra Bounce: What Did You Eggs-pect? - Experiement #346

"Can an egg be changed chemically by placing it in different compounds?

You will need:
2 whole raw eggs (in shell)
glass of water
glass of vinegar

What to do: Put one egg in a glass of water and let it stand for a full 24 hours. Place the other egg in the vinegar and let it stand for the same length of time.

What happens: The egg in the water remains the same, while the egg in the vinegar compound now feels and looks like a rubber ball, and no longer has a shell! If you drop it a short distance into the sink, it will actually bounce! Now you know how this experiment got its name.

Why: In the vinegar, a chemical change took place in the eggs. The acetic acid (vinegar) reacted with the calcium carbonate of the eggshell. The change cause the shell to soften and disappear, while the egg in the glass of water did not chemically change. Chemists would say that the shell of the egg in the vinegar becomes "decalcified"."

What happened when CKS tried it?: As soon as we put the eggs in the bowls, the egg in the vinegar had bubbles STRAIGHT away!

The next day, the shell was gone and it looked sort of yellowish and it was squishy and bigger than the egg from the water.

I tried bouncing it in the sink. I bounced it 4 times and then on the 5th time, it popped and the yolk came out. All that was left was a skin and the yolk.

The other egg was hard and small and really white with the shell still on - it didn't seem any different to me.

CKS rating: 5 stars - Better than TV!

Tip of the Iceberg - Experiment #326

"If all the icebergs in the seas were to melt, would the sea level rise? This very simple experiment will give us the answer, and it's based on a very important compound chemists study - water!

You will need:
glass
warm water
6-8 ice cubes

What to do: Place as many ice cubes as you can into a glass; then fill the glass to the brim with warm water. Wait.

What happens: When the ice cubes melt, the water does not overflow.

Why: The ice cubes simply displace the water in the glass, or the amount of ice that melted was exactly equal to the mass of the ice cubes below the water. Like the ice cubes in the glass, the main part of an iceberg is under water. If all the icebergs were to melt, as did the ice cubes in our experiment, the sea level would remain the same. (It's a different story if ice stored on land [like glaciers] were to melt).

What happened when CKS tried it?: It took almost 3 hours for the ice cubes to melt. There is about half a dollar-size puddle of water in the plate under the glass. The glass is so cold that it's misting up and gets foggy and water starts to form. CMS calls it 'condensation' on the outside of the glass. The water in the plate is coming from the air! Water is condensing from the air and forms drops on the glass. No water spilled over the top of the glass so icebergs melting in the sea would not raise sea level!

CKS rating: 2 stars - I'd rather eat my broccoli.