When people hear the word metal, it is usually associated with a cold and solid substance that conducts electric current. However, metals and their alloys can be very different from each other. There are those that belong to the heavy group, these substances have the highest density. And some, for example, lithium, are so light that they could swim in water, if only they did not react actively with it.
What metals are most active?
But which metal exhibits the most intense properties? The most active metal is cesium. In terms of activity, it takes first place among all metals. Also, his "brothers" are France, which is in second place, and ununited. But so far, little is known about the properties of the latter.
Cesium properties
Cesium is an element that, like gallium metal, is easy to melt in hands. True, this can be done only under one condition: if cesium is in a glass ampoule. Otherwise, the metal can quickly react with the surrounding air - it will ignite. And the interaction of cesium with water is accompanied by an explosion - this is the most active metal in its manifestation. This is the answer to the question of why it is so difficult to place cesium in containers.
In order to place it inside the test tube, it is necessary that it be made of special glass and filled with argon or hydrogen. The melting point of cesium is 28.7 about C. At room temperature, the metal is in a semi-liquid state. Cesium is a golden white substance. In a liquid state, the metal reflects light well. Cesium vapors have a greenish-blue hue.
How was cesium discovered?
The most active metal was the first chemical element, the presence of which in the surface of the earth's crust was detected using the method of spectral analysis. When scientists received a spectrum of metal, then in it they saw two lines of sky-blue color. Thus, this element got its name. The word caesius in Latin means "sky blue."
Discovery story
Its discovery belongs to the German researchers R. Bunsen and G. Kirchhoff. Even then, scientists were interested in which metals are active and which are not. In 1860, researchers studied the composition of the water from the Durkheim reservoir. They did this using spectral analysis. Scientists found elements such as strontium, magnesium, lithium, and calcium in a water sample.
Then they decided to analyze a drop of water with a spectroscope. Then they saw two bright blue lines that are not far from each other. One of them almost coincided in its position with the strontium metal line. Scientists decided that the substance they identified was unknown and attributed it to the group of alkali metals.
In the same year, Bunsen wrote a letter to his fellow photochemist G. Roscoe, in which he spoke about this discovery. And officially, cesium was announced on May 10, 1860 at a meeting of scientists at the Berlin Academy. Six months later, Bunsen was able to isolate about 50 grams of cesium chloroplatinite. Scientists processed 300 tons of mineral water and isolated about 1 kg of lithium chloride as a by-product to ultimately get the most active metal. This suggests that cesium is very low in mineral waters.
The difficulty of obtaining cesium constantly pushes scientists to search for minerals containing it, one of which is pollucite. But the extraction of cesium from ores always turns out to be incomplete; during the operation of cesium, it dissipates very quickly. This makes it one of the most inaccessible substances in metallurgy. The earth's crust, for example, contains 3.7 grams of cesium per ton. And in one liter of sea water, only 0.5 μg of the substance is the most active metal. This leads to the fact that the extraction of cesium is one of the most labor-intensive processes.
Getting in Russia
As indicated, the main mineral from which cesium is derived is pollucite. And also this most active metal can be obtained from rare avogadrite. In industry, it is pollucite that is used. It was not mined after the collapse of the Soviet Union in Russia, despite the fact that even in those days, giant reserves of cesium were discovered in the Voronoi tundra near Murmansk.
By the time domestic industry was able to afford the extraction of cesium, a license to develop this field was acquired by a company from Canada. Now the extraction of cesium is performed by the Novosibirsk company ZAO Rare Metals Plant.
Cesium use
This metal is used to make various photocells. As well as cesium compounds are used in special fields of optics - in the manufacture of infrared devices, night vision binoculars. Cesium is used in the manufacture of sights, which allow you to notice the equipment and manpower of the enemy. It is also used for the manufacture of special metal halide lamps.
But this does not exhaust the range of its application. Based on cesium, a number of medications have also been created. These are medicines for treating diphtheria, peptic ulcers, shocks, and schizophrenia. Like lithium salts, cesium salts have normotymic properties - or, simply, can stabilize the emotional background.
France metal
Another of the metals with the most intense properties is France. It got its name in honor of the homeland of the discoverer of metal. M. Pere, born in France, discovered a new chemical element in 1939. It is one of those elements that even chemical researchers themselves find it difficult to draw any conclusions about.
France is the heaviest metal. Moreover, the most active metal is France, along with cesium. This rare combination - high chemical activity and low nuclear stability and possesses France. Its longest-lived isotope has a half-life of only 22 minutes. France is used to detect another element - sea anemone. As well as salts of France, it was previously proposed to be used to detect cancerous tumors. However, due to the high cost of this salt is unprofitable to produce.
Comparison of the most active metals
Ununny is not yet discovered metal. He will occupy first place in the eighth line of the periodic table. The development and research of this element is carried out in Russia at the Joint Institute for Nuclear Research. This metal will also have to have very high activity. If we compare the already known France and cesium, then the highest ionization potential - 380 kJ / mol - will have France.
In cesium, this indicator is 375 kJ / mol. But France doesn’t react as fast as cesium. Thus, cesium is the most active metal. This is the answer (chemistry is most often the subject in the program of which you can meet a similar question), which can be useful both in the classroom at the school and in the vocational school.