Sulfur dioxide reacts with sodium hydroxide.

Their curiosity and desire to explore the world.

Born with it.

But China students,

I didn't start to contact chemistry until the third grade.

It comes up with various chemical formulas.

Make sb dizzy,

Therefore, I lost my interest in learning chemistry.

In fact,

As a natural science, chemistry,

Its beauty is beyond your imagination.

Today's sharing will take you to see it.

All kinds of magical chemical reactions,

Maybe you will love chemistry for it.

1. decomposition of mercury thiocyanate ("Pharaoh's snake")

Principle: Mercury thiocyanate is decomposed by heat, and some products burn.

2Hg(SCN)2→2Hg+CS2+c3n 4

CS2 + 3O2 → CO2 + 2SO2

2C3N4 → 3(CN)2 + N2

Story: 182 1 year, the Germans synthesized mercury thiocyanate, and soon discovered the special phenomenon of its combustion. For a long time, it was sold as a kind of fireworks in Germany, but it was finally banned because of many accidents in which children were poisoned by eating by mistake.

Danger: high. Mercury compounds are toxic, as are mercury sulfide, sulfur dioxide and cyanide gas produced by the reaction. Don't try it yourself without a fume hood and professional guidance!

2. Matches burn

Principle: Matchhead contains red phosphorus, sulfur and potassium chlorate. The heat generated when striking matches makes red phosphorus and sulfur burn, and potassium chlorate is decomposed into oxygen to assist combustion.

Story: The earliest friction matches only contained sulfur. 1826, British chemist John e walker used potassium chlorate for the first time, but his matches were very dangerous, and fireballs often fell on light clothes and carpets.

Danger: low. But please don't give children matches to play with, it may cause a fire.

3. Hydrogen meets fire

Principle: Hydrogen is flammable and easy to diffuse, and it can explode and burn in the air.

Story: What happened on the Hindenburg airship is an enlarged version of this scene.

Danger: medium. It is easy to explode and hurt people, and it is most easily ignited by remote control, as shown in the figure.

4. Mercury and aluminum rust

Principle: Aluminum is a highly active metal, but the alumina layer on its surface makes it unable to completely react with oxygen in the air. Mercury will destroy this protective layer and make aluminum "rust" quickly.

This is time-lapse photography. The real length of this process is about half an hour. If the picture moves down, you will see a lot of aluminum rust powder below.

Story: This is one of the reasons why it is forbidden to carry mercury on the plane. Legend has it that during World War II, some American commandos carried mercury to destroy German planes.

Danger: moderate to low. Mercury is toxic and inedible, so it needs to be tested in a place with smooth air circulation to avoid mercury vapor poisoning.

5. Iron bars and copper sulfate

Principle: Put the derusting iron bar into copper sulfate solution, iron is more active than copper, and the replaced copper forms beautiful loose precipitate.

The solution is blue at first (the color of hydrated copper ions), and as the reaction progresses, the blue color gradually fades.

Story: Copper ion itself is not blue, and anhydrous copper sulfate is white powder. The blue color in the aqueous solution is copper ions hexahydrate.

Danger: low. Copper solution is poisonous and inedible.

6. Gas ignition

Principle: Combustion requires combustible materials to contact with oxygen, and the narrow bottle mouth makes oxygen only enter gradually, and the combustion surface moves down gradually.

Danger: medium to high. Improper handling of combustible gas can easily lead to explosion.

7. Burning magnesium is put into water.

Principle: Magnesium can actually react with water at room temperature, but unless it is magnesium powder, the speed is very slow. At high temperature, they will react violently to produce magnesium oxide and hydrogen. Hydrogen continues to burn, and together with the burning magnesium, it produces dazzling light and shadow effects.

Story: This reaction is the basic principle of an experimental engine designed by Japan. Magnesium oxide produced by the reaction between magnesium and water is decomposed into magnesium and oxygen again under the action of laser. The whole reaction only needs water, and the laser is powered by sunlight. However, this engine seems to be far away.

Danger: medium. Magnesium burns at high temperature and reacts violently with water, which may spill red-hot liquid magnesium and cause burns.

8. Acetone "dissolves" foam

Principle: A thin layer of acetone can't really "dissolve" the whole foam. In fact, it just.