Here are
some fun Weird Science experiments you can reproduce at home! Most of these are adapted from
Steve Spangler Science©. Because Steve is a Science Education Correspondent for
Denver’s Channel 9 News, you can watch some of his fun videos on their website
(http://www.9news.com/news/education/spangler/default.aspx)
Can you
skewer a balloon without popping it?
Materials
needed:
1 or more
balloons
1 barbeque
skewer
a little
vegetable oil (any kind will work)
What to
do:
- Blow up a balloon and tie the end.
- Dip the sharp end of the
barbeque skewer in vegetable oil.
- Look for the “darker spots” of
the balloon, or places where the latex molecules are more dense (hint: the
top and bottom of the balloon is a good place to start looking).
- Slowly and tenderly pierce the skewer through a dark spot of the balloon. Then guide it all the way through the middle of the balloon until you reach another dark spot on the other side. Gingerly pierce the other side and…
Voila!
You’ve skewered a balloon!
The
science behind it:
The latex
molecules that make up the balloon are the least stressed near the top and
bottom of the balloon, whereas they are the most stressed (stretched out) along
the sides of the balloon. At the ends of the balloons where the molecules
aren’t as stretched out, these long molecular chains wrap themselves around the
place where you inserted the skewer, consequently keeping the air from escaping
the balloon.
Fireworks
on a plate!
Materials
needed:
3 plates
1 cup of
whole milk
1 cup of 1%
milk
1 cup of
water
food
coloring (several colors are best)
Dawn soap
1 or 2
Q-tips
What to
do:
- Cover the first plate with
whole milk.
- Cover the second plate with 1%
milk.
- Cover the third plate with
water.
- Put several drops of food
coloring (different colors) in each liquid, in the center of each plate.
Be careful not to stir them.
- Dip one end of a Q-tip in Dawn
soap, then dip the same end in the center of the plate with the water and
food coloring. What happens? Watch it for a minute or so.
- Dip a Q-tip in the soap again.
Then dip it in the center of the plate with the 1% milk. What happens this
time? Again, watch for a minute. Does the food coloring move around more
than it did in the water?
- Finally, dip the Q-tip in soap one more time. Now dip it in the center of the plate with the whole milk. Watch the food coloring for a while. How long does it move around the plate compared to the water and 1% milk?
The
science behind it:
Soap is a
bipolar molecule. This means that one end of the molecule is polar, and one end
is non-polar. The polar end is attracted to water, while the non-polar end is
attracted to the fat in the milk. The soap therefore weakens the bonds that
keep the fats and proteins in the milk solution. The food coloring is just a
“tracer” that allows you to watch it happening!
Upside-down
water!
Materials
needed:
1 ball jar,
with ring that goes around the lid
1 piece of
screen (window screen, shade cloth, or similar; large enough to cover top of
jar)
1 piece of
card stock or similar paper
Water
What to
do:
- Take the lid off the ball jar
and place the screen over the top.
- Screw the ring on the jar to
hold the screen in place.
- Fill the jar to half or ¾ full
with water.
- Place a piece of card stock
over the top, so that it completely covers the screen.
- Holding the cardstock securely
in place, turn the jar upside down (over the sink or outside is best!).
- Ask your child to hypothesize
what will happen when you remove the cardstock.
- Slowly remove the cardstock by
sliding it off to the side and then away from the jar.
- Keep the jar stead and perfectly vertical for this to work!
The
science behind it:
The water
stays in the jar because of surface tension. Water molecules stick together
because of a force called cohesion. This force causes the water molecules to
essentially “glue” themselves together between openings in the screen, and this
surface-tension “membrane” that is formed is what holds the water in the jar.
It is also the reason why raindrops are spherical.
