Daniela Ramos`s VIP PowerPoint presentation.

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4 Cool Science Experiments
By: Daniela Ramos
Experiment #1
• First, take out the plate and the soap for experiment #1.
• Then, pull out the pepper bag of the plate. (please don’t smell it or you will start to
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sneeze.)
Next, I will come around and pour water into your plates.
After I pour the water, open the pepper, and sprinkle it on top of the water.
Then, put a bit of soap on your finger and touch the top of the water.
The pepper should have moved to the rim of the bowl and left the middle untouched.
What Happened?
• Pepper is used in this experiment just because it is easy to see the reaction. This
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means that if we would have used any other floating substance like flour, it would
have worked.
A molecule of pepper on top of the water is not attracted in any direction except
downwards because that’s where all the other molecules of it’s type are. This creates a
type of skin on top of the water called surface tension.
Soap destroys the surface tension of water. This makes it look like pepper is rejected
by soap, but in fact, pepper stays afloat on the skin of water which scoots away from
the soap, taking the pepper with it.
Experiment #2
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For this experiment, all you need is your hand.
First, put it flat on your desk.
Next, move all your fingers.
After that, curl up your middle finger and push it back under your hand as far as it
will go.
• Now, try to move all your fingers again.
• Your ring finger should be frozen in place.
What Happened?
• All the tendons in your fingers are independent except the middle and ring fingers.
• This means that those tendons are connected making it very difficult to move your
ring finger once your middle finger is down.
• PS: There are a few people that can do it; I never said it was impossible, just very
hard.
Experiment #3
• We will be doing this experiment in groups, and picking 5 volunteers (per group) to help me .
• 1st volunteers, take out the box of matches, the tape, and a coin.
• 2nd volunteers, take out 2 matches from the box, place the box in the middle of 2 desks all the way to
the front (so everyone can see), and give the matches to volunteer #3.
• 3rd volunteers, take a small piece of tape and make it into a tube (with the sticky part on the outside).
Stick a match on the very top of the tape so it stands upright. Put it down on the right side of the box.
Put the coin on the left side, and balance the other match leaning on the first match and on the coin.
• 4th and 5th volunteers, your job is to get the coin out from under the match without letting the match
fall over (you can’t touch the match).
• Stumped? Well, let me tell you that there is a possible way to do this, and me and my mom will show
you.
What Happened?
• Wood is made up of giant molecules which form long chains. They make needle shape
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crystals.
When wood is heated, these long stretched chains start to move around, and causes a
contraction.
When a match burns, the part that is just at the end of the flame as it burns down
gets hot. But it gets hotter at the top than at the bottom. So, the top part starts
contracting before (and more than) the bottom, and this causes the match to bend
upwards.
Experiment #4
• We are going to do this one very similarly to #3. Again we will have groups and
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volunteers.
1st volunteers, take out 2 coins, 3 matches, tape, the plate, and a cup.
2nd volunteers, place the plate in the same place as last time and put the coin on the
left side of the plate.
My mom will come around and pour water and food coloring (it’s easier to see) into
the plate.
3rd volunteers, tape the 3 matches together and stick the matches on a tube of tape.
Stick a coin on the bottom, and place the whole thing on the right side of the plate.
My mom will light the matches and the 4th volunteers will have to place the cup on
top of the matches right when they are lit.
The water should get sucked up into the cup.
What Happened?
• For a fire to start, you need combustible material (matches), oxygen (air), and a spark
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(lighter).
When my mom lit the matches in the cup, the fire only could take the air that was in
the cup.
Air takes up space. As the air rapidly turned to fire, the cup got empty and sucked up
the water just to fill that empty space.
Do it at home
• All you need are 2 unsharpened pencils (or colored pencil that don’t have erasers or 2
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sides).
Hold one in each hand, with the flat sides touching.
Now, push them together as hard as you can for 10 seconds.
As you pull apart you should feel a magnetic pull.
Thanks for Watching!!!
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