That day, a building in the university caught fire. "Boo hoo" fire truck rushed to the scene. A strange thing happened: the fire brigade tried to pick it up from a nearby building.
Water. However, the gate of the building is heavily guarded and firefighters are not allowed to enter. "Burning eyebrows, don't let us in?" The fireman asked anxiously. "No way. No one can enter without the certificate of the Ministry of National Defense! " The guard said with a livid face. The fire was fierce and the firemen were in a hurry. They surrounded the guards and asked loudly, "Wait for national defense."
The certificate of the Ministry has arrived, and the building has been burned out! "The doorman finally made some concessions:" Well, you go to the local X Bureau for instructions and get a certificate. "Can't, firefighters had to drive a fire truck to X bureau to get the license. The firemen stuffed their papers into the hands of the guards and hurried to the building. At this time, the guards caught up with them and stopped them. He said very seriously, "gentlemen, although you
There are documents, but according to the regulations, all people who enter the building must sign the register. Gentlemen, please.
Son, sign it! "Firefighters in distress situation, had to go back to sign.
Although these guards are so loyal to their duties, they still reveal the secrets of the building. People are suspicious:
That building is heavily guarded. What's in it? You know, the U.S. Department of Defense struggled to keep the secret of that building: once, it was guaranteed.
Health workers carefully inspected the library in the building and found that many chemistry books looked quite new, but
The chapters on elemental uranium in every book have been turned over or dyed. The security guard thought that these books might also lead to the exposure of the secrets of the building, decided to destroy them all and bought a batch of brand-new chemistry books. They kept the secret so carefully that they were inadvertently exposed by the fire in the building next door.
So German spies began to pay attention to this building?
Needless to say, the scientists in that building are studying the chemical element uranium in great secrecy. Why is uranium research so strictly confidential?
1On August 5th, 945, the explosion of the atomic bomb shook the world. The "protagonist" in the atomic bomb,
It's uranium Because of this, the building has become the key secret department of the US Department of Defense and the focus of German spy agencies.
The second story happened in 178 1, England. At that time, there was a famous chemist named priestley in England. He likes to give it to his friends.
Friends perform chemical magic. You see, when his friend came to visit his laboratory, he took out an empty bottle and gave it to Linda.
Look at home clearly. However, when he moved the bottle mouth close to the flame of the candle, there was a loud bang.
Friends were startled, and some even got under the table. Priestley laughed proudly. After laughing, he told his friends the secret: it turned out that hydrogen was injected into the bottle in advance. Hydrogen and air
When the oxygen in the mixture is ignited, it will burn and make a loud noise.
I don't know how many times he performed this program, making it a masterpiece. Once, after performing his "masterpiece", he noticed water droplets on the bottle wall when cleaning the bottle. Strange, the bottle is clean when it becomes "magic". Where did the water drops on the bottle wall come from?
What about coming out? Priestley carefully wiped the bottle and repeated the experiment. Gee, there are drops of water on the bottle wall.
After repeated experiments, he finally found that after hydrogen burned, it turned into water and condensed on the bottle wall! Before priestley, although people were drinking and using water every day, they didn't know what water was. Since ancient times, people have even regarded water as an "element". 1770, the famous French chemist lavoisier tried to uncover the secret of water. He sealed the water in a container and heated it for 100 days. Water is still water, and the weight is the same as before 100 days. He can't figure out what water is. What about priestley? Although he uncovered the secret of water, after he performed many "magic tricks",
Did you notice the water drops on the bottle wall?