The Funny Mad World of Science

One of the most spectacular chemistry demonstrations is also one of the simplest.It's the dehydration of sugar with sulfuric acid.

All you have to do to perform this demonstration is to put ordinary table sugar in a glass beaker and to add concentrated sulfuric acid. You will see that the sulfuric acid removes water from the sugar in a highly exothermic reaction which release heat, and fumes. This reaction is a dangerous one because of the toxicity of the fumes and because of the heat but the reaction smells a lot like caramel. The white sugar turns into a black carbonized tube that pushes itself out of the beaker.Try it, it's very impressive.

Explanation:

In fact, as said before, the sulfuric acid will react with sugar following these two reactions:

Sugar is dehydrated:

C12H22O11 =  12 C (graphite)  + 11 H2O ( l )

Sulfuric acid is hydrated:

H2SO4 , n H2O + m H2O  =  H2SO4 , (n+m) H2O  +  heat

Gallium spoon melting !

To make this trick you just need a very pure gallium spoon (99.99% pure !) easily obtained by Gallium and spoon molds.

Then put it into not concentrated acid... but just hot water ! And you will see the spoon melts to a liquid puddle in only few seconds !

Explanations :

The melting point of the Gallium is very low : less than 30°C ! So, everytime you move beyond this temperature the Gallium changes phases from solid to liquid ! You can also make this transformation just by holding Gallium in your hands.

sneeze_with_the_sun

Do you want to know why you feel hotter when you are wearing a black T-shirt than a clearer one ?

Let's have a small experiment!

Ingredients:

• 2 glasses
• Water
• White and black paper
• thermoter
• scotch

Instructions:

Wrap a rectangle of paper around each glass and hold it with scotch or an elastic and pour the same quantity of water in them.

Put the both glasses into the sunshine and wait for an hour (or more).

Come back and measure the temperature of water in the two glasses.

Explanations :

Dark surfaces absord more light thant the clearer ones. That's why the water into the "black glass" is warmer. Light surfaces reflect more light.

Materials:

• Clear Plastic water Bottle with its cap
  
• Rubbing Alcohol

Take an empty water bottle. Make sure that the plastic is not too tick to make the experiment easier.
Pour a little bit of rubbing alcohol into the bottle, close it and then shake it so that the alcohol covers all the internal parts of the bottle.

Twist the bottle from the bottom with both hands in opposite directions in order to increase the pressure at the top of the bottle.

Keep twisting until you can no longer do it.

Now, unscrew the cap of the bottle very slowly until it is about to pop off. When you feel that phenomenon just let it pop off quickly and observe a white cloud escaping the bottle !

Be careful to make sure that you don't point anyone while oppening the bottle because the cap can be ejected with the pressure !

Explanation:

As you now, clouds are made of little drops of water vapor, and there is invisible molecule of water all around us.

By twisting the bottle,  you will compress the air molecules of the bottle and they will tend to expand while releasing the cap.

Then, the air molecules will get cooler and will stick with the water and the alcohol vapor molecules.

Like the clouds in the sky, tiny water drops will be formed and a cloud will escape from your bottle !

Mother's Day is approaching and you don't know what to buy to her? What about bath salts with her favourite perfume so she can relax in her bath?

Ingredients:

• Washing soda
• plastic bag
• rolling pin or a heavy glass bottle
• bowl
• spoon
• essential oil (rose, mint, mango, bergamot...)
• food coloring

Instructions:

Put some washing soda into the plastic bag, close it cautiously and then crush the bit of soda with the rolling pin.

Pour the powder into a bowl and and stir it with a few drops of essential oil and food coloring tusing the spoon.

Put the bath salts into a dry container and wait until Mother's Day !

Tips:

Bergamot, lavanda and Ylang-Ylang are reputed to be relaxing oil.

Jasmine, cinnamon and ginger are reputed to be enerziging.

Eucalyptus, Rosemary, Niaouly and Scots Pine are good for breathing.

Do you want to become a spy and write some secret messages?

Ingredients:

• a lemon
• water
• bowl
• paper
• coton bud or penholder
• light bulb or radiator

Instructions:

Squeeze the lemon to extract its juice.Pour it into the bowl and add a few drops of water. Mix well.

Your ink is ready!

Dip your coton or the penholder (ask to your grandparents to get one) into the lemon mixture and write what you want to keep secret on the white sheet.

Let the paper dry.

When you want to reveal your message, just heat the sheet by putting it near a light bulb.

Explanations :

Lemon juice is oxidised whent it's heated that's why it turns brown.

You have already seen this phenomenon of oxidation, for instance with apples. When you eat an apple, the flesh is clear and if you let your apple for a moment, it turns brown.

To make this invisible ink, you can also use orange juice or milk.

If you use soap or saliva, you'll need an ultraviolet source to reveal your writing!

Picture 1: Drop of Water on a Lotus leaf

 Picture 2: Self-cleaning Effect 

Picture 3: The double micro-structuration of the leaf

Sound files:

Lotus_1

Lotus_2

Create a real volcano into your garden!

Ingredients:

• vinegar
• baking soda
• plastic bottle
• soil or sand
• red pigment

Instructions:

Melt the baking soda with the red pigment, and place it into the plastic bottle.

Place soil all around the bottle to hide it. Give it a conical shape to make it look like a volcano.

Finally, pour some vinegar into the bottle and watch !

Explanations :

The baking soda (sodium bicarbonate) is a base while the vinegar (acetic acid) is an acid. When they react together they form carbonic acid which is very unstable, it instantly breaks down into water and carbon dioxide, which creates all the fizzing as it escapes the solution.

Normally  when water is added to sand the outcome is predictable. The sand becomes
wet. This is not the case with MAGIC SAND!  Magic Sand has the unique quality of staying
dry under water. You can buy Magic Sand on Ebay  or make your own, spraying silicon (with a silicon spray) on classical sand.


Explanation:

Magic sand works because the silicone coating makes it repel the water molecules.The scientific
term for this is hydrophobic meaning to "fear water".  Regular sand is referred to as being Hydrophilic or
"water loving" because it will absorb water. It's simply for that reason that magic sand is always dry.