Chimie

How does an eraser work?

I bring here a non negligible complement for the pupils having chosen the eraser as TPE. The detail of the composition of the blue ink and the eraser as well as the chemical reaction ink-eraser is treated here
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toughness of the diamond

Why the diamond is it more hard than graphite (mine of pencil) whereas it is constituted of the same chemical element: the carbon. In spite of this incredible toughness the diamond has a dangerous enemy....
Come to discover the secrets of the diamond....
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working of the breathalyzer

How a ball of breathalyzer can value the quantity of alcohol contained in blood? a chemical reaction takes place. details and explanation inside
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Manufacture of the caffeine-free coffee

Caffeine is a naturally component present in coffee. Caffeine has a slightly stimulating effect mainly on the central nervous system. But how its possible to withdraw the caffeine of coffee?
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The vitamin C: an antioxidant

The C vitamin, also known as ascorbic acid, is probably the most popular vitamin, while being least known of all vitamins. Come to discover its protective role in our organism
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Working of the airbag

What makes an airbag inflates so quickly? A gas is injected there at a very big speed. How? By a chemical reaction.... chimique....
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The lily of the valley: a toxic plant

How does a so pretty plant can be toxic? It is true that in certain case the dress doesn't make the monk!
More detail on this plant inside
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The substances contained in the cigarette

II consider the cigarette as a drug, in the same way as the cocaine, ecstasies and other. I will even say that it is a poison that kills slowly.
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The antidote of cyanide

Does everybody know cyanide, this extremely virulent poison? I am going to tell you the history of Mr. X that wanted to poison Mr. Y. However all didn't happen like foreseen....
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The toxicity of manioc

Cassava is a basic food of several countries in Africa. It is little expensive source of carbon hydrates. However cassava is a toxic root that can cause serious problems of health.
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Physics

why is the sky blue?

it is only a light phenomenon.... The light that we receives on earth comes from the sun. The white light produced by the sun is a set of all colors whose sum forms the white. In other words the sun produces the red, the green, the yellow, the blue....
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Can air freeze?

Let's take the example of water, it can be at the liquid state, solid after having put it to the freezer and gaz, it is the steam of water. What happen for air?
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The gas embolism

The gas embolism is a phenomenon dreaded among the adepts of the scuba diving. Is it a formation of air bubbles in blood vessels of the organism. How these bubbles appear and what are the consequences for the health?
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Some pen is pierced

ou probably noticed that some pens (not all) possess a small discreet hole on the side. This hole has its importance. try to think before seeing the answer.
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How to transform gold in lead?

How many alchemists have broken his teeth while wanting to transform the gold in lead? We thought one moment that it was an utopia but today it is possible. So, I assure you that is quite possible. How?
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Why the bow in sky is a bow?

Very interesting question that has been asked me by Sohel of Albi. Since we are childhood we see the bow in sky. Then today, when we see a bow in sky that remained only a bow in sky and nothing besides.
The big question is "why a bow and not a right line?"
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To make sink a boat with... an gold ingot

he goal of the game is not to hit like a mad on the cockle of the boat to make sink it, it is there about a real chemical reaction that takes place between the boat, the sea water and the gold ingot
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Biology

How does the yeast make inflate bread?

he beer yeast (used in bakery) named Saccharomyces cerevisiae - is a naturally present mushroom in air. But how this mushroom helps the baker in its creations?
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Differences between chemical yeasts and baker yeasts

Can you go buy me yeast please? ask your mom. In the supermarket you have a problem of size. Indeed, your mom didn't specify you if she wanted chemical yeast or baker's yeast. Is this equal?
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Why is meat red?

meat is red, in any case meat cow is red. But why meat is red? The answer seems simple, we be tempt to answer: 'Because it contains more blood'.  not so true ....
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Differences between natural EPO and recombinant EPO

It is a question that often comes back in the discussion forums, because many high school students have some exercices on this topic. Epo it is not the man's invention ! Its a protein produced by our body. It is essential to the manufacture of our red globules.
But how its possible to differentiate the natural EPO and the EPO used for the doping?
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The Weight loss programs can enlarge

You decided to undertake a weight loss programs all alone. The first time all went very well.... then one day you began to take your kilograms! Why? You don't know anything of it! Yet this situation has a very simple explanation.
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