Radioactive metal and its properties. What is the most radioactive metal

Among all the elements of the periodic system, a large part belongs to the ones most people talk about with fear. How else? After all, they are radioactive, which means a direct threat to human health.

Let's try to figure out which elements are dangerous and what they are, and also find out what is their harmful effect on the human body.

General concept of a group of radioactive elements

This group includes metals. They are quite numerous, they are located in the periodic system immediately after the lead and to the very last cell. The main criterion by which one or another element is considered to be classified as a radioactive group is its ability to have a certain half-life.

In other words, radioactive decay is the transformation of a metal nucleus into another, a daughter, which is accompanied by the emission of radiation of a certain type. At the same time, some elements are transformed into others.

A radioactive metal is one that has at least one isotope. Even if there are six varieties of all varieties, and only one of them will be the bearer of this property, the entire element will be considered radioactive.

Kinds of radiation

The main variants of radiation, which is emitted by metals during decays, are:

• Alpha particles;
• Beta particles or neutrino decay;
• Isomeric transition (gamma rays).

There are two options for the existence of such elements. The first is natural, that is, when a radioactive metal is found in nature and in the simplest way, under the influence of external forces, transforms into other forms over time (manifests its radioactivity and decays).

The second group is artificially created by scientists metals, capable of rapid decay and the powerful release of a large amount of radiation. This is done for use in certain areas of activity. Installations in which nuclear reactions are produced by the transformation of some elements into others are called synchrophasotrons.

The difference between the two indicated methods of half-decay is obvious: in both cases it is spontaneous, but only artificially produced metals give precisely nuclear reactions in the process of destructuring.

The fundamentals of the designation of such atoms

Since for most of the elements only one or two isotopes are radioactive, it is customary to indicate a specific type in the notation, and not the entire element as a whole. For example, lead is just a substance. If you take into account that it is a radioactive metal, you should call it, for example, "lead-207".

The half-lives of the particles under consideration can vary greatly. There are isotopes that exist only 0.032 seconds. But on a par with them there are also those that are disintegrating for millions of years in the terrestrial bowels.

Radioactive metals: list

A complete list of all the elements belonging to the group under consideration can be quite impressive, because only about 80 metals belong to it. First of all, these are all in the periodic system after lead, including the group of lanthanides and actinides. That is, bismuth, polonium, astatine, radon, france, radium, rutherfordium and so on by serial numbers.

Above the indicated boundary there are many representatives, each of which also has isotopes. However, some of them may be just radioactive. Therefore, it is important what kind of chemical element has a variety . Radioactive metal, more precisely one of its isotopic varieties, is practically in every representative of the table. For example, they have:

• calcium;
• selenium;
• hafnium;
• tungsten;
• osmium;
• bismuth;
• indium;
• potassium;
• rubidium;
• zirconium;
• europium;
• Radium and others.

Thus, it is obvious that there are a lot of elements exhibiting the properties of radioactivity - the overwhelming majority. Some of them are safe because of too long half-lives and are found in nature, while the other is man-made artificially for various needs in science and technology and is extremely dangerous for the human body.

Characteristics of radium

The name of the element is given by its discoverers - the Curie couple, Pierre and Maria. It was these people who first discovered that one of the isotopes of this metal - radium-226 - is the most stable form, which has special properties of radioactivity. This happened in 1898, and a similar phenomenon only became known. A detailed study of it was just engaged in the spouses of chemists.

The etymology of the word takes its roots from the French language, on which it sounds like a radium. In total, 14 isotopic modifications of this element are known. But the most stable forms with mass numbers:

• 220;
• 223;
• 224;
• 226;
• 228.

The form 226 has a clearly pronounced radioactivity. By itself, the radium is a chemical element under the number 88. The atomic mass [226]. As a simple substance is capable of existence. It is a silvery white radioactive metal with a melting point of about 670 ^° C.

From a chemical point of view, it exhibits a sufficiently high degree of activity and is able to react with:

• Water;
• Organic acids, forming stable complexes;
• Oxygen forming an oxide.

Properties and applications

Radium is also a chemical element that forms a number of salts. Known are its nitrides, chlorides, sulfates, nitrates, carbonates, phosphates, chromates. Also there are double salts with tungsten and beryllium.

The fact that radium-226 can be dangerous to health, its discoverer Pierre Curie did not recognize right away. However, I was able to convince myself of this when I conducted the experiment: day he walked with a tube with metal attached to the shoulder part of his hand. At the place of contact with the skin appeared non-healing ulcer, get rid of which the scientist could not more than two months. From their experiments on the phenomenon of radioactivity, the spouses did not refuse, and therefore both died from a large dose of radiation.

In addition to the negative value, there are a number of areas in which radium-226 finds application and benefits:

1. Indicator of ocean water level shift.
2. Used to determine the amount of uranium in the rock.
3. It is part of the lighting mixtures.
4. In medicine it is used to form medical radon baths.
5. Applied for the purpose of removing electrical charges.
6. With its help, flaw detection is carried out and the seams of the parts are welded.

Plutonium and its isotopes

This element was discovered in the forties of the twentieth century by American scientists. It was first isolated from uranium ore, in which it was formed from neptunium. The latter is the result of the decay of the uranium core. That is, all of them are closely interconnected among themselves by common radioactive transformations.

There are several stable isotopes of a given metal. However, the most widespread and most important variety is plutonium-239. There are known chemical reactions of a given metal with:

• Oxygen,
• Acids;
• Water;
• Alkalis;
• Halogens.

In terms of its physical properties, plutonium-239 is a brittle metal with a melting point of 640 ⁰ С. The main ways of affecting the body are the gradual formation of cancer, accumulation in the bones and causing their destruction, lung diseases.

The field of use is mainly the nuclear industry. It is known that with the decay of one gram of plutonium-239, an amount of heat is released that is comparable to 4 tons of burnt coal. That is why this kind of metal finds such wide application in reactions. Nuclear plutonium is a source of energy in nuclear reactors and thermonuclear bombs. It is also used in the manufacture of electric energy batteries, the service life of which can reach five years.

Uranium - the source of radiation

This element was discovered in 1789 by a chemist from Germany Klaproth. However, people were able to study its properties and learn how to apply them in practice only in the 20th century. The main distinguishing feature is that radioactive uranium is capable of forming nuclei in a natural decay:

• Lead-206;
• Krypton;
• Plutonium-239;
• Lead-207;
• Xenon.

In nature, this metal is light gray in color and has a melting point above 1100 ^° C. It is found in minerals:

1. Uranium mica.
2. Uraninite.
3. Nasturan.
4. Otenite.
5. Tyuyannmunit.

There are three stable natural isotopes and 11 artificially synthesized, with mass numbers from 227 to 240.

In the industry, radioactive uranium is widely used, which can quickly decay with the release of energy. So, it is used:

• In geochemistry;
• Mining;
• Nuclear reactors;
• In the manufacture of nuclear weapons.

Influence on the human body is no different from the previous metals - accumulation leads to an increased dose of radiation and the emergence of cancerous tumors.

Transuranium elements

The most important of the metals that follow uranium in the periodic system are those that were discovered only recently. Literally in 2004, the sources came out, confirming the birth of 115 elements of the periodic system.

They became the most radioactive metal of all known to date - Unupunctions (Uup). Its properties remain unexplored until now, because the half-life is 0.032 seconds! It is simply impossible to consider and reveal the details of the structure and the features that are manifested under such conditions.

However, its radioactivity is many times greater than that of the second element in this property, plutonium. Nevertheless, in practice, not ununpenties are used, but the more "slow" his companions on the table are uranium, plutonium, neptunium, polonium and others.

Another element - unbibia - theoretically exists, but it can not be proved by scientists of different countries since 1974. The last attempt was made in 2005, but it was not confirmed by the general advice of scientists-chemists.

Thorium

It was opened in the XIX century by Berzelius and named in honor of the Scandinavian god Thor. It is a weakly radioactive metal. Five of its 11 isotopes possess this feature.

The main application in nuclear power is not based on the ability to emit a huge amount of thermal energy during decay. The peculiarity is that the thorium nuclei are able to capture neutrons and turn into uranium-238 and plutonium-239, which already enter directly into nuclear reactions. Therefore, thorium can also be referred to the group of metals we are considering.

Polonium

Silver-white radioactive metal under number 84 in the periodic table. It was discovered by all the same ardent investigators of radioactivity and everything connected with it, by the spouses Maria and Pierre Curie in 1898. The main feature of this substance is that it exists freely for about 138.5 days. That is, this is the half-life of the metal.

In nature it occurs in the composition of uranium and other ores. Used as an energy source, and quite powerful. It is a strategic metal, as it is used for the production of nuclear weapons. The quantity is strictly limited and is under the control of each state.

It is also used for ionizing air, eliminating static electricity in the room, making space heaters and other similar items.

Effects on the human body

All radioactive metals have the ability to penetrate the human skin and accumulate inside the body. They are very poorly derived from the products of life, do not appear with sweat.

Over time, the respiratory, circulatory, nervous systems start to affect, causing irreversible changes in them. Affect cells, causing them to function incorrectly. As a result, malignant tumors are formed, and oncological diseases occur.

Therefore, each radioactive metal is a great danger to humans, especially if we speak about them in pure form. You can not touch them with unprotected hands and be in the room with them without special protective devices.