Similarities and differences between nuclear bombs and atomic bombs. What is the difference between nuclear weapons and atomic weapons? Queen of all queens

To the question How do nuclear reactions differ from chemical ones? given by the author Yoabzali Davlatov the best answer is Chemical reactions take place at the molecular level, while nuclear reactions take place at the atomic level.

Answer from Battle Egg[guru]
During chemical reactions, some substances are converted into others, but the transformation of some atoms into others does not occur. During nuclear reactions, the atoms of some chemical elements are converted into others.

Answer from Zvagelski michael-michka[guru]
Nuclear reaction. - the process of transformation of atomic nuclei, which occurs during their interaction with elementary particles, gamma quanta and with each other, often leading to the release of a colossal amount of energy. Spontaneous (occurring without the impact of incident particles) processes in nuclei - for example, radioactive decay - are usually not referred to as nuclear reactions. To carry out a reaction between two or more particles, it is necessary that the interacting particles (nuclei) come closer to a distance of the order of 10 to minus 13 degrees of cm, that is, the characteristic radius of action of nuclear forces. Nuclear reactions can occur both with the release and with the absorption of energy. Reactions of the first type, exothermic, are the basis of nuclear energy and are the source of energy for stars. Reactions involving the absorption of energy (endothermic) can occur only under the condition that the kinetic energy of colliding particles (in the center of mass system) is higher than a certain value (reaction threshold).

Chemical reaction. - transformation of one or several initial substances (reagents) into chemical compounds that differ from them in chemical composition or structure (reaction products). Unlike nuclear reactions, chemical reactions do not change the total number of atoms in the reacting system, as well as the isotopic composition of chemical elements.
Chemical reactions occur during mixing or physical contact of reagents spontaneously, upon heating, with the participation of catalysts (catalysis), the action of light (photochemical reactions), electric current (electrode processes), ionizing radiation (radiation-chemical reactions), mechanical action (mechanochemical reactions), in low-temperature plasma (plasma-chemical reactions), etc. The transformation of particles (atoms, molecules) is carried out provided that they have energy sufficient to overcome the potential barrier separating the initial and final states of the system (activation energy).
Chemical reactions are always accompanied by physical effects: absorption and release of energy, for example, in the form of heat transfer, a change in the state of aggregation of reagents, a change in the color of the reaction mixture, etc. It is by these physical effects that chemical reactions are often judged.

As you know, the main engine of the progress of human civilization is war. And many "hawks" justify the mass extermination of their own kind by precisely this. The issue has always been controversial, and the emergence of nuclear weapons has irrevocably turned a plus sign into a minus sign. Indeed, why do we need progress that will ultimately destroy us? Moreover, even in this suicidal affair, the person showed his characteristic energy and ingenuity. Not only did he come up with a weapon of mass destruction (atomic bomb) - he continued to improve it in order to kill himself quickly, efficiently and guaranteed. An example of such active activity is the very rapid leap to the next step in the development of atomic military technologies - the creation of thermonuclear weapons (hydrogen bomb). But let's leave aside the moral aspect of these suicidal tendencies and move on to the question brought up in the title of the article - how is the atomic bomb different from the hydrogen one?

A bit of history

There, overseas

As you know, Americans are the most enterprising people in the world. They have a great flair for everything new. Therefore, one should not be surprised that the first atomic bomb appeared in this part of the world. Let's give a little historical background.

• The experiment of two German scientists O. Hahn and F. Strassmann on splitting the uranium atom into two parts can be considered the first stage on the way to creating an atomic bomb. This, so to speak, still unconscious step was taken in 1938.

• Nobel laureate Frenchman F. Joliot-Curie in 1939 proves that the fission of the atom leads to a chain reaction, accompanied by a powerful release of energy.

• The genius of theoretical physics A. Einstein put his signature on a letter (in 1939) addressed to the President of the United States, initiated by another atomic physicist L. Szilard. As a result, even before the outbreak of World War II, the United States decided to start developing atomic weapons.

• The first test of the new weapon was carried out on July 16, 1945 in the northern part of New Mexico.

• Less than a month later, 2 atomic bombs were dropped on the Japanese cities of Hiroshima and Nagasaki (August 6 and 9, 1945). Humanity entered a new era - now it was able to destroy itself in a few hours.

The Americans fell into a real euphoria from the results of the total and lightning-fast defeat of peaceful cities. The staff theorists of the US Armed Forces immediately set about drawing up grandiose plans, consisting in the complete erasure of 1/6 of the world - the Soviet Union - from the face of the earth.

Caught up and overtaken

The Soviet Union did not sit idly by either. True, there was some lag, caused by the solution of more urgent matters - the Second World War was going on, the main burden of which lay on the country of the Soviets. However, the Americans did not wear the leader's yellow jersey for long. Already on August 29, 1949, at the test site near the city of Semipalatinsk, a Soviet-style atomic charge was first tested, created in shock terms by Russian atomic scientists under the leadership of Academician Kurchatov.

And while the frustrated "hawks" from the Pentagon were revising their ambitious plans to destroy the "stronghold of the world revolution", the Kremlin struck a preemptive strike - in 1953, on August 12, a new type of nuclear weapon was tested. In the same place, near the city of Semipalatinsk, the world's first hydrogen bomb, code-named "Product RDS-6s", was detonated. This event caused a real hysteria and panic not only on Capitol Hill, but also in all 50 states of the "stronghold of world democracy". Why? What is the difference between an atomic bomb and a hydrogen one that plunged the world superpower into horror? We will answer right away. A hydrogen bomb is far superior to an atomic bomb in its combat power. Moreover, it is much cheaper than an equivalent atomic sample. Let's take a closer look at these differences.

What is an atomic bomb?

The principle of operation of the atomic bomb is based on the use of energy resulting from an increasing chain reaction caused by the fission (splitting) of heavy nuclei of plutonium or uranium-235 with the subsequent formation of lighter nuclei.

The process itself is called single-phase, and it proceeds as follows:

• After the detonation of the charge, the substance inside the bomb (isotopes of uranium or plutonium) goes into the decay stage and begins to capture neutrons.

• The decay process is growing like an avalanche. The splitting of one atom leads to the decay of several. A chain reaction occurs, leading to the destruction of all the atoms in the bomb.

• A nuclear reaction begins. The entire bomb charge turns into a single whole, and its mass passes its critical point. Moreover, all this orgy does not last long and is accompanied by the instantaneous release of a huge amount of energy, which ultimately leads to a tremendous explosion.

By the way, this feature of a single-phase atomic charge - to quickly gain critical mass - does not allow an infinite increase in the power of this type of ammunition. The charge can have a capacity of hundreds of kilotons, but the closer it is to the megaton level, the less effective it is. It simply does not have time to completely split: an explosion will occur and part of the charge will remain unused - it will be scattered by an explosion. This problem was solved in the following type of atomic weapon - in the hydrogen bomb, which is also called thermonuclear.

What is a hydrogen bomb?

In a hydrogen bomb, a slightly different process of energy release takes place. It is based on work with hydrogen isotopes - deuterium (heavy hydrogen) and tritium. The process itself is divided into two parts, or, as they say, is two-phase.

• The first phase is when the main supplier of energy is the fission reaction of heavy lithium deuteride nuclei into helium and tritium.

• Second phase - thermonuclear fusion based on helium and tritium is launched, which leads to instant heating inside the warhead and, as a result, causes a powerful explosion.

Thanks to the two-phase system, a thermonuclear charge can be of any power.

Note. The description of the processes taking place in the atomic and hydrogen bombs is far from complete and the most primitive. It is given only for a general understanding of the differences between the two weapons.

Comparison

What's in the bottom line?

Any schoolchild knows about the damaging factors of an atomic explosion:

• light radiation;
• shock wave;
• electromagnetic impulse (EMP);
• penetrating radiation;
• radioactive contamination.

The same can be said for a thermonuclear explosion. But!!! The power and consequences of a thermonuclear explosion are much stronger than an atomic one. Here are two well-known examples.

The Kid: Black Humor or Uncle Sam's Cynicism?

The atomic bomb (codenamed "Kid"), dropped on Hiroshima by the Americans, is still considered the "benchmark" indicator for atomic charges. Its power was approximately 13 to 18 kilotons, and the explosion was perfect in all respects. Later, tests of more powerful charges were carried out more than once, but not much (20-23 kilotons). However, they showed results that slightly exceeded the achievements of "Malysh", and then stopped altogether. A cheaper and more powerful "hydrogen sister" appeared, and there was no point in improving atomic charges. Here is what happened "at the exit" after the explosion of the "Kid":

• The mushroom mushroom reached an altitude of 12 km, the diameter of the "cap" was about 5 km.
• The instantaneous release of energy from a nuclear reaction caused a temperature at the epicenter of the explosion of 4000 ° C.
• Fireball: about 300 meters in diameter.
• The shock wave knocked out glass at a distance of 19 km, and was felt much further.
• About 140 thousand people died at once.

Queen of all queens

The consequences of the explosion of the most powerful hydrogen bomb tested to date, the so-called Tsar Bomba (code name AN602), surpassed all previously conducted explosions of atomic charges (not thermonuclear) taken together. The bomb was Soviet, with a capacity of 50 megatons. Its tests were carried out on October 30, 1961 in the area of ​​Novaya Zemlya.

• The mushroom mushroom grew 67 km in height and the diameter of the upper "cap" was about 95 km.
• The light radiation hit at a distance of 100 km, causing third-degree burns.
• The ball of fire, or ball, has grown to 4.6 km (radius).
• The sound wave was recorded at a distance of 800 km.
• The seismic wave circled the planet three times.
• The shock wave was felt at a distance of up to 1000 km.
• The electromagnetic pulse created powerful interference for 40 minutes, several hundred kilometers from the epicenter of the explosion.

One can only fantasize what would happen to Hiroshima if such a monster were dropped on her. Most likely, not only the city would disappear, but also the Land of the Rising Sun itself. Well, now we will bring everything that we have said to a common denominator, that is, we will draw up a comparative table.

table

So, we figured out what is the difference between an atomic bomb and a hydrogen bomb. Unfortunately, our little analysis only confirmed the thesis stated at the beginning of the article: the progress associated with the war followed a disastrous path. Humanity has risen to the brink of self-destruction. It remains only to press a button. But let's not end the article on such a tragic note. We very much hope that reason, the instinct of self-preservation, in the end, will win and a peaceful future awaits us.

Nature develops in dynamics, living and inert matter continuously undergoes transformation processes. The most important transformations are those that affect the composition of the substance. The formation of rocks, chemical erosion, the birth of a planet or the respiration of mammals are all observable processes that entail changes in other substances. Despite the differences, they all have something in common: changes at the molecular level.

1. Elements do not lose their identity in the course of chemical reactions. These reactions involve only the electrons of the outer shell of the atoms, while the nuclei of the atoms remain unchanged.
2. The reactivity of an element to a chemical reaction depends on the oxidation state of the element. In ordinary chemical reactions, Ra and Ra 2+ behave completely differently.
3. The various isotopes of the element have nearly the same chemical reactivity.
4. The rate of a chemical reaction is highly dependent on temperature and pressure.
5. The chemical reaction can be reversed.
6. Chemical reactions are accompanied by relatively small changes in energy.

Nuclear reactions

1. In the course of nuclear reactions, the nuclei of atoms undergo changes and, therefore, as a result, new elements are formed.
2. The reactivity of an element to a nuclear reaction is practically independent of the oxidation state of the element. For example, Ra or Ra 2+ ions in Ka C 2 behave in a similar way in nuclear reactions.
3. In nuclear reactions, isotopes behave in completely different ways. For example, U-235 fissions calmly and easily, but U-238 does not.
4. The rate of a nuclear reaction is independent of temperature and pressure.
5. The nuclear reaction cannot be canceled.
6. Nuclear reactions are accompanied by large energy changes.

Difference between chemical and nuclear energy

• Potential energy that can be converted to other forms is primarily heat and light when bonds are formed.
• The stronger the bond, the greater the converted chemical energy.

• Nuclear energy is not associated with the formation of chemical bonds (which are due to the interaction of electrons)
• Can be transformed into other forms when a change occurs in the atomic nucleus.

Nuclear change occurs in all three main processes:

1. Nucleus splitting
2. The joining of two nuclei to form a new nucleus.
3. The release of high energy electromagnetic radiation (gamma radiation), creating a more stable version of the same core.

Energy conversion comparison

The amount of released chemical energy (or converted) in a chemical explosion is:

• 5kJ for each gram of TNT
• The amount of nuclear energy in the released atomic bomb: 100 million kJ for each gram of uranium or plutonium

One of the main differences between nuclear and chemical reactions has to do with how the reaction takes place in the atom. While a nuclear reaction takes place in the nucleus of an atom, the electrons in the atom are responsible for the chemical reaction that takes place.

Chemical reactions include:

• Transmission
• Losses
• Gain
• Separation of electrons

According to the theory of the atom, matter is explained as a result of rearrangement to give new molecules. The substances involved in a chemical reaction and the proportions in which they are formed are expressed in the corresponding chemical equations underlying various types of chemical calculations.

Nuclear reactions are responsible for nuclear decay and have nothing to do with electrons. When a nucleus decays, it can go to another atom, due to the loss of neutrons or protons. In a nuclear reaction, protons and neutrons interact within the nucleus. In chemical reactions, electrons react outside the nucleus.

Any fission or fusion can be called the result of a nuclear reaction. A new element is formed due to the action of a proton or neutron. As a result of a chemical reaction, a substance is changed into one or more substances due to the action of electrons. A new element is formed due to the action of a proton or neutron.

When comparing energy, a chemical reaction involves only a low energy change, whereas a nuclear reaction has a very high energy change. In a nuclear reaction, the energetic magnitude changes are 10 ^ 8 kJ. This is 10 - 10 ^ 3 kJ / mol in chemical reactions.

While some elements are converted to others in the nuclear, the number of atoms remains unchanged in the chemical. In a nuclear reaction, isotopes react in different ways. But as a result of a chemical reaction, isotopes also react.

Although a nuclear reaction is independent of chemical compounds, a chemical reaction is highly dependent on chemical compounds.

Summary

A nuclear reaction takes place in the nucleus of an atom, the electrons in the atom are responsible for chemical compounds.
1. Chemical reactions include - transfer, loss, amplification and separation of electrons, without involving the nucleus in the process. Nuclear reactions involve nuclear decay and have nothing to do with electrons.
2. In a nuclear reaction, protons and neutrons react inside the nucleus; in chemical reactions, electrons interact outside the nucleus.
3. When comparing energies, a chemical reaction uses only a low energy change, whereas a nuclear reaction has a very high energy change.

For an accurate answer to the question, you will have to seriously delve into such a branch of human knowledge as nuclear physics - and deal with nuclear / thermonuclear reactions.

Isotopes

From the course of general chemistry, we remember that the matter around consists of atoms of different "sorts", and their "grade" determines exactly how they will behave in chemical reactions. Physics adds that this happens due to the delicate structure of the atomic nucleus: inside the nucleus there are protons and neutrons that form it - and electrons are constantly “rushing” around in "orbits". Protons provide a positive charge to the nucleus, and electrons provide a negative charge, which compensates for it, which is why the atom is usually electrically neutral.

From a chemical point of view, the "function" of neutrons boils down to "diluting" the uniformity of nuclei of the same "kind" with nuclei with slightly different masses, since only the nuclear charge will affect the chemical properties (through the number of electrons due to which the atom can form chemical bonds with other atoms). From the point of view of physics, neutrons (like protons) participate in the preservation of atomic nuclei due to special and very powerful nuclear forces - otherwise, the atomic nucleus would instantly fly apart due to the Coulomb repulsion of like-charged protons. It is neutrons that allow isotopes to exist: nuclei with the same charges (that is, identical chemical properties), but different in mass.

It is important that it is impossible to create nuclei from protons / neutrons in an arbitrary way: there are their "magic" combinations (in fact, there is no magic here, physicists just agreed to call this way especially energetically favorable ensembles of neutrons / protons), which are incredibly stable - but "moving away "From them, you can get more and more radioactive nuclei, which" fall apart "by themselves (the further they are from the" magic "combinations - the more likely their decay over time).

Nucleosynthesis

A little higher it was found out that according to certain rules it is possible to "construct" atomic nuclei, creating more and more heavy ones from protons / neutrons. The subtlety is that this process is energetically beneficial (that is, it proceeds with the release of energy) only up to a certain limit, after which more energy is required to create increasingly heavy nuclei than is released during their synthesis, and they themselves become very unstable. In nature, this process (nucleosynthesis) takes place in stars, where monstrous pressures and temperatures "ram" the cores so tightly that some of them merge, forming heavier ones and releasing energy due to which the star shines.

The conventional "efficiency frontier" runs through the synthesis of iron nuclei: the synthesis of heavier nuclei is energy-intensive and iron eventually "kills" the star, and heavier nuclei are formed either in trace amounts due to the capture of protons / neutrons, or massively at the time of the death of the star in the form a catastrophic supernova explosion, when the fluxes of radiation reach truly monstrous magnitudes (a typical supernova emits one light energy at the time of an outbreak as much as our Sun in about a billion years of its existence!)

Nuclear / thermonuclear reactions

So, now we can give the necessary definitions:

Thermonuclear reaction (aka fusion reaction or in English nuclear fusion) Is a type of nuclear reaction where the lighter nuclei of atoms, due to the energy of their kinetic motion (heat), merge into heavier ones.

Nuclear fission reaction (it is also a decay reaction or in English nuclear fission) - this kind of nuclear reaction, where the nuclei of atoms spontaneously or under the action of a particle "outside" disintegrate into fragments (usually two or three lighter particles or nuclei).

In principle, in both types of reactions, energy is released: in the first case, due to the direct energetic advantage of the process, and in the second, that energy is released that was spent on the formation of atoms heavier than iron during the "death" of the star.

The essential difference between nuclear and thermonuclear bombs

It is customary to call a nuclear (atomic) bomb such a device of an explosive type, where the bulk of the released energy during an explosion is released due to a nuclear fission reaction, and a hydrogen (thermonuclear) bomb is one where the bulk of the energy is produced through a thermonuclear fusion reaction. An atomic bomb is a synonym for a nuclear bomb, a hydrogen bomb is a thermonuclear one.

In the media, you can often hear loud words about nuclear weapons, but the destructive ability of one or another explosive charge is very rarely specified, therefore, as a rule, thermonuclear warheads with a capacity of several megatons and atomic bombs dropped on Hiroshima and Nagasaki at the end of World War II are placed in one row , the capacity of which was only 15 to 20 kilotons, that is, a thousand times less. What is behind this colossal gap in the destructive capabilities of nuclear weapons?

There is a different technology and charge principle behind this. If obsolete "atomic bombs", such as those that were dropped on Japan, operate on pure fission of heavy metals, then thermonuclear charges are a "bomb in a bomb", the greatest effect of which creates the synthesis of helium, and the decay of nuclei of heavy elements is only the detonator of this synthesis.

A bit of physics: heavy metals are most often either uranium with a high content of the isotope 235 or plutonium 239. They are radioactive and their nuclei are not stable. When the concentration of such materials in one place sharply increases to a certain threshold, a self-sustaining chain reaction occurs, when unstable nuclei, breaking into pieces, provoke the same decay of neighboring nuclei with their fragments. Energy is released during this decay. Lots of energy. This is how the explosive charges of atomic bombs work, as well as the nuclear reactors of nuclear power plants.

As for a thermonuclear reaction or a thermonuclear explosion, there the key place is given to a completely different process, namely, the synthesis of helium. At high temperatures and pressures, it happens that colliding, hydrogen nuclei stick together, creating a heavier element - helium. At the same time, a huge amount of energy is released, which is evidenced by our Sun, where this synthesis constantly takes place. What are the advantages of a thermonuclear reaction:

First, there is no limitation in the possible power of the explosion, because it depends solely on the amount of material from which the synthesis is carried out (most often, lithium deuteride is used as such a material).

Secondly, there are no products of radioactive decay, that is, the very fragments of nuclei of heavy elements, which significantly reduces radioactive contamination.

And thirdly, there are no those colossal difficulties in the production of explosive material, as is the case with uranium and plutonium.

There is, however, a minus: it takes a tremendous temperature and incredible pressure to start such a synthesis. To create this pressure and heat, a detonating charge is required, which works on the principle of the ordinary decay of heavy elements.

In conclusion, I would like to say that the creation of an explosive nuclear charge by this or that country most often means a low-power "atomic bomb", and not a really terrible thermonuclear one capable of wiping out a large metropolis.