What is heavy water?Why should the atomic bomb heavy water?Only the bomb is needed

Is there a difference between water? Of course, the water we drink on weekdays is "light water", and the opposite is "heavy water".

What is heavy water? As the name suggests, it is heavier than ordinary water. The molecular mass of light water we drink daily is 18.0153, and the molecular mass of heavy water is 20.0275. It can be seen that the quality of heavy water is about 11%higher than the quality of light water. Where did the quality come from? In fact, the quality of neutron. There are various different elements in nature, such as hydrogen, oxygen, carbon, and iron. For composition, there is proton and neutrons in the nucleus. The number of protons in which the type of proton determines the type of element. For example, the hydrogen atom with a proton is the atomic atom.

In addition to many different elements in nature, the same element also has several different isotopes, which is determined by the number of neutrons.

For example, hydrogen has three types of homogenin, namely 氕, 氘, and 氚. These three types of homicide have the same proton, which is a proton, but there is only one proton in the nucleus of the 氕 氕, but there is no neutron. And there are 2 neutrons. The molecular formula of a water molecule consisting of 2 子 atoms and 1 oxygen atom is the H2O we are familiar with, which is the most common and most common light water, and there are two water molecules composed of 2 氘 atoms and 1 oxygen atoms. The molecular formula is written as D2O. This is heavy water. Because heavy water is 2 neutron than light water, the quality is naturally larger.

Although it is only 2 neutron than light water, heavy water is no longer the "source of life". Not only is it not the source of life, drinking heavy water will also cause death.

However, we don't need to worry, because in nature, the proportion of heavy water is very small. They are mixed in light water, but the proportion is less than 0.02%. Although heavy water cannot drink, there are other purposes, such as the manufacturing of atomic bombs. The atomic bomb is a weapon that uses nuclear fission reactions to produce huge destructive power. Its power mainly comes from the internal "pretending medicine". There are currently two elements that can be used for atomic bomb -loading, namely uranium 235 and 钚 239. No matter which element is adopted, it must be purified. Taking uranium 235 as an example, the proportion of its uranium ore is only 0.7%, and the rest are uranium 238. To create nuclear weapons, the concentration of uranium 235 must be purified at least 85%. The purity required during the process of making atomic bullets is even higher.

In order to increase the concentration of uranium 235, a large number of advanced gas centrifuge must be used for repeated concentration, which is a difficult threshold for many countries.

If the uranium 235 is used as an atomic bomb, then it does not use heavy water, but if you use 钚 239, heavy water is essential. Unlike uranium 235, uranium 235 exists in nature. What we have to do is to try to separate it from uranium 238, but 钚 239 does not exist in nature. It requires manual production. How to do it? This is to start with uranium 238. The power of the atomic bomb is huge because of the principle of "chain reaction".

The so -called chain reaction is simply that the uranium 235 absorbs neutrons. After the neutron is absorbed, the energy is released and two neutrons are thrown. These two neutron will be absorbed by other uranium 235, leaving the whole body.

However, the uranium 238 mixed with uranium 235 will also absorb neutron, but it will not fission after absorbing neutron, which will directly become uranium 239, and the neutron generated by the fission of uranium 235 is eaten by uranium 238 silently. If the chain reaction cannot be achieved. For uranium 235, uranium 238 is redundant, but in terms of 钚 239, uranium 238 is very useful. After absorbing the neutron of uranium 238, it will become uranium 239, uranium 239 is unstable, and it will become 镎 239 through β decay. Making 需要 239 needs to use atomic reactors, and the atomic reactor can be divided into light water reactors and heavy water reactors based on the cooling agent used.

Both the light water reactor and the heavy water reactor can be used for 钚 239, but the 钚 239 made by light water reactors cannot be used to make atomic bullets.

This is because the 钚 239 generated in the light water reactor is also mixed with a large number of 钚 240.极 240 is a very unstable element that occurs from time to time. If the 钚 240 mixed in 钚 239 is too much, you and I know what will happen, that is, it is unpredictable to explode at any time. Therefore, the 4 240 content in 钚 239 exceeds 19%, which is a waste material that must be landed. 7%to 19%can be used as fuel. To create a original bullet, the content of 钚 240 must be controlled below 7% The light water reactor is absolutely not reached, so if you want to make atomic bullets, you must use heavy water reactors to make 钚 239. Why do 钚 240 must be landfilled and cannot be purified? There is only one neutron between 钚 239 and 0 240. This is like a few cows in a cow group than other beef hair. It is impossible to pick them out.

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