[paul.fr]

an old favourite

What you need

A narrow necked glass bottle
3 matches
a peeled, hard bolied egg

What you do

Drop three lit matches into the glass bottle. Quickly put the hard-boiled egg on the mouth of the bottle.

What happens?

[Karen W.]

HEE HEE HEE! That one is also my favorite, I have a question about the results of this one. I have done it several times..and each time am at a loss for retrieving my lunch from the bottle, LOL Can one reverse the process Paul? LOL

[Karen W.]

I also have a question if one pierced an egg before cooking and did this same experiment, would the suction be strong enough to pull the yolk from the shell leaving the shell whole. You know like when you blow the contents out?

[paul.fr]

May be i should have included that  [:I]

Turn the the bottle upside-down, Put the bottle over the top of your head, like you are leaning you head back and looking up at the bottle.

Wit the bottle about half and inch from your mouth, blow into the bottle hard, and don't stop. The egg should come out.

or you can heat the bottle under warm water and the egg will come out.

[paul.fr]

I also have a question if one pierced an egg before cooking and did this same experiment, would the suction be strong enough to pull the yolk from the shell leaving the shell whole. You know like when you blow the contents out?

I like that, give it a try and let me know would you?

[Karen W.]

May be i should have included that  [:I]

Turn the the bottle upside-down, Put the bottle over the top of your head, like you are leaning you head back and looking up at the bottle.

Wit the bottle about half and inch from your mouth, blow into the bottle hard, and don't stop. The egg should come out.

or you can heat the bottle under warm water and the egg will come out.

LOL LOL.. HEE HEE HEE!!  I don't know if I have enough air to continuely blow like that, BUT Paul, I think you should try it, but shouldn't you be "SUCKING" instead of blowing??? Will the egg really come out if you are blowing! LOL

So you never tried the other one.. HUMMMMM I will have to try it out and see!!!

[paul.fr]

shouldn't you be "SUCKING" instead of blowing??? ! LOL

No, it's all to do with air pressure. If you don't have the lungs for blowing you could always use a hairdryer. or, add about an inch of water to the bottle and break up an alka seltzer tablet/bicarbonate of soda . Put the tablet in the bottle then turn the bottle upside down. The pressure from the expanding gas should blow the egg out of the bottle.

[Karen W.]

 OH that is interesting, I guess me brain doesn't work like that, cause that never occured to me. HMMMMM I will try it next time!

I could try the hair dryer that might do it! we will see!

[paul.fr]

Found this one on the net. similar to one done by Dave


What you need

water
a squirt of dishwashing liquid
1/2 a teaspoon of salt
1 teaspoon of ice cold ethanol or methylated spirits or rubbing alcohol (isopropanol)
two cups and
a clear container with a lid


What you do

1.Dissolve half a teaspoon of salt in half a cup of water. Add a squirt of dishwashing liquid. This liquid will be used to break up the cells and release the DNA.

2.Take about a tablespoon (20 - 25 mls) of plain water into your mouth. Don't swallow! Swish the water around your cheeks vigorously for about 30 seconds. This removes some cheek cells. Spit the water into a clean cup or glass.

3.Add about 1 teaspoon (5 mls) of this fluid to a small clean container with a lid (a 20 ml test-tube or a clear plastic film canister would work). Add about half a teaspoon (2.5 mls) of the salt/dishwashing liquid (saline/detergent) solution. Put the cap on the container and tip it up and down gently 3 or 4 times to mix (but you don't want a lot of froth so don't shake it). This will break up the many hundreds of cheek cells, releasing the DNA from the nucleus.

4.Gently run a teaspoonful of ice-cold ethanol into the tube. Methanol or rubbing alcohol - isopropanol - should also work; make sure they are ice cold by placing the bottle in the freezer for a few hours before the experiment. Watch the point where the two layers meet. You may see strands of DNA forming, as cloudy filaments stretching up into the top (ethanol) layer. DNA is not soluble in ethanol, so when the ethanol meets the DNA solution it starts to precipitate (form a DNA salt).

5.You may be able to hook out the strands of DNA with a glass hook (or one made from a plastic twist-tie) by slowly dipping up and down through the two layers. If this doesn't work, gently invert the tube several times until the alcohol is mixed in. The precipitated DNA will look like a small ball of white thread.

topic link

HOW IS DNA SEPARATED FOR DNA FINGERPRINTING? http://www.thenakedscientists.com/forum/index.php?topic=5889.0
An excellent experiment by Daveshorts (Dave Ansell) http://www.chaosscience.org.uk/pub/public_html//article.php?story=20050524184709373

[paul.fr]

An easy one, to confuse the kids with.

What you need

A small apple or orange
a piece of paper


What you do

Hold the apple/orange and the paper at the same height from the ground and drop them at the same time.

Which hits the ground first? yes the apple/orange

Now scrunch the paper into a round ball the same size as the apple/orasnge and repeat dropping them from the same height.

Which hit the ground first this time?

[daveshorts]

The above procedure will extract both DNA and proteins, so the gunk you see may not be all DNA, to get more pure DNA you need to break down the proteins. To do this you need an enzyme called a protease. fresh pineapple and kiwi juices have these, which is why they hurt to eat - they are digesting your mouth. So you could add these and keep the mixture warm for 10mins or you could just extract teh DNA from kiwi fruit.

Here is something I wrote a while back about this which you may find interesting
http://www.chaosscience.org.uk/pub/public_html//article.php?story=20050524184709373

[Karen W.]

Thanks Dave and Paul I am excited to try this one.. I have never done this before.. Me is very happy!!!!! YAYYYYYYYY!! I want to see DNA!!! YAYYYYYY!

[paul.fr]

I would not do that DNA one first, Karen. I would do Dave's kiwi fruit one then the other. Dave's is much better, i thought dave had it in the kitchen science section of the main site but can't find it!

so here is a link to the kiwi fruit one on daves own site: http://www.chaosscience.org.uk/pub/public_html//article.php?story=20040206021823942

Which is also well worth looking around.

[paul.fr]

The above procedure will extract both DNA and proteins, so the gunk you see may not be all DNA, to get more pure DNA you need to break down the proteins. To do this you need an enzyme called a protease. fresh pineapple and kiwi juices have these, which is why they hurt to eat - they are digesting your mouth. So you could add these and keep the mixture warm for 10mins or you could just extract teh DNA from kiwi fruit.

Here is something I wrote a while back about this which you may find interesting
http://www.chaosscience.org.uk/pub/public_html//article.php?story=20050524184709373

thanks for that, Dave. Just out of curisity, will you be adding any more dates to the chaos tour/roadshow?

[Karen W.]

 I will try both!! Thanks!

[daveshorts]

thanks for that, Dave. Just out of curisity, will you be adding any more dates to the chaos tour/roadshow?

We are attempting to finalise the tour's dates fairly soon, if we raise enough money. The plan is to go to Devon, Dorset, bits of Suffolk Gloucester, amongst others.

Do you have anywhere you would want us to go?

[paul.fr]

What you need

A microwave
3 grapes


What you do

take one grape, with it's stem/stalk attached and put it in the microwave for 10 seconds. What happens?

OK, that was fun, but this next one is just....cool.

take the remaining two grapes, and remove the stem/stalk. place them in the microwave with the hole where the stem/stalk was facing eachother. they should be about half a centimeter apart.

now cook them for 8 to 10 seconds, but no longer than that. if you repeat this use fresh grapes.

What happens?


do not cook the grapes for longer than 10 seconds, cooking for longer has a slight chance of damaging your microwave.
please also note that the grapes will be very hot and inedible

[paul.fr]

What you need

a jar with a lid
a thermometer
steel/wire wool
vinegar
a bowl

What you do

put the therrthermometer into the jar and put on the lid. Let the jar sit for about 15 minutes and then check the temperature.

Next, place the steel wool into a small bowl. Pour some vinegar onto it,  using enough to get the steel wool very wet. Squish it around a bit and then squeeze out as much vinegar as you can.
Put the wet steel wool into the jar, up against the thermometer. Again, note the temperature. Put the top on the jar and leave it for five minutes.

After five minutes, check the temperature again. What do you notice?
 
Put the lid back on the jar and wait another 10 minutes. Check the temperature again. Then wait another 10 minutes and check again.

What is happening to the temperature?
What has happened to teh steel wool?

[paul.fr]

What you need

an egg
a tall glass
salt
water


What you do

half fill the glass with water, then add enough salt to saturate the water, 4 to 6 spoonfulls should do. wait a minute or two

then carefully fill the glass with more water, pouring gently down the side of the glass is best as you do not want the two layers of water to mix.

gently put the egg in to the top of the glass and let go.

what happens?

[paul.fr]

kids love science and ice cream so why not do both! Sure most of us will have done this before but i thought it worth posting anyway.

What you need

ice cubes
salt
one large glass bowl
one smaller glass bowl
tea towel
double cream (from memory i think it's double cream)
milk


what you do

mix a tablespoon of cream with two of milk in the small bowl. put a lyer of ice cubes in the large bowl and sprinkle salt over the ice cubes.

put the small bowl in the middle of the large bown and pack more layers of salt ice cubes around it until the ice is as high as the bowl.

cover the bowls with the tea towel and leave for one hour, stirring every five minutes. you can add cocoa powder at the initial stage for chocolate ice cream.

one hour later, eat the ice cream

if you bowls are quite large them obviously you can double up the quantities of cream and milk to make more ice cream.

can someone let me know if i am right about the double cream as i will be making some at the weekend. thanks in advance.