Iron is the main structural material. Metal is used literally everywhere – from missiles and submarines to Cutlery and wrought-iron ornaments on the grill. In no small measure, this is facilitated by an element in nature. However, the true reason is, nevertheless, its strength and durability.
In this article, we will characterize iron as a metal and indicate its useful physical and chemical properties. Separately, we tell you why iron is called black metal, how it differs from other metals.
This metal is silver-gray in color, quite soft, plastic, and has magnetic properties. In fact, pure iron is found and used very rarely, because the metal is chemically active and enters into a variety of reactions.
The advantages of metal include other qualities.
Strength and hardness while maintaining elasticity – we are not talking about chemically pure iron, but about alloys. Moreover, these qualities vary quite widely depending on the brand of steel, the method of heat treatment, the method of production, and so on.
A variety of steels and ferrites allows you to create and select a material for virtually any task-from the bridge frame to the cutting tool. The ability to obtain the specified properties with the addition of very small impurities is an extremely great advantage.
The ease of machining allows you to get products of various types: bars, pipes, fittings, beams, sheet iron, and so on.
The magnetic properties of iron are such that the metal is the main material in the production of magnetic drives.
The cost of alloys depends, of course, on the composition, but it is still significantly lower than that of most non-ferrous metals, even with higher strength characteristics.
The malleability of iron provides the material with very high decorative possibilities.
Liquid mercury is a very mobile liquid. Alchemists called mercury "mercury" after the Roman God mercury, who was famous for his speed in moving. In English, French, Spanish, and Italian, the name "mercury"is used for mercury. The modern Latin name comes from the Greek words "hyudor" — water and "Argyros" — silver, i.e. "liquid silver".Mercury and its compounds are highly toxic. Mercury vapors and compounds accumulate in the human body, are absorbed by the lungs, enter the blood, disrupt the metabolism and affect the nervous system. Signs of mercury poisoning are already apparent when the mercury content is 0.0002–0.0003 mg/l. Mercury vapors are phytotoxic and accelerate the aging of plants.
Silver is one of the rare elements that form a group of precious or precious metals. This group also includes gold, platinum and five metals of the platinum group.
Like all precious metals, silver under normal conditions is not affected by air, water, or any other factors that usually lead to rapid corrosion and oxidation of "normal" metals. In addition, silver is quite rare in the earth's crust and has a number of remarkable properties, which puts it in the category of precious metals.
Physical properties of silver
Pure silver is a fairly heavy, shiny white metal. According to D. I. Mendeleev in the textbook "Fundamentals of chemistry", silver has the most "pure" white color among all metals.
Silver has a remarkable reflectivity-about 95% in the visible part of the spectrum, which is the highest among metals. It is this property of silver that people used to make mirrors. Most of the discovered ancient mirrors were made of polished silver about 5 thousand years ago. Silver mirrors were very expensive and, of course, only very rich people could afford to own them. The more familiar glass mirrors appeared only about 600 years ago.
Silver has the highest thermal conductivity among metals. Therefore, you should carefully use silver Cutlery with hot dishes. For example, a silver teaspoon in a Cup of very hot tea instantly heats up and can even cause a burn.
One of the main properties of silver is its unique electrical conductivity. At a temperature of + 20°C, it has the highest electrical conductivity among all elements.
Silver melts at a temperature of 961°C, which is the lowest among all precious metals. Therefore, silver, like gold with a melting point of 1063°C, people have learned to process melting from time immemorial. The temperature of the coal Gorenje was quite enough for this.
Pure silver is a very soft, malleable and malleable metal. In terms of softness and malleability, silver is slightly inferior to gold, but in terms of plasticity (that is, the ability to change shape under load without collapsing), it is superior to gold. These qualities determine the widespread use of silver for the manufacture of jewelry.
There is no person who does not see gold in jewelry. The bright yellow metal has been known to humans for thousands of years. However, in nature, gold has many faces. The size of its particles ranges from microns to tens of centimeters, the color, due to impurities, is not always yellow. There are several minerals similar to gold in appearance. No wonder there is a saying "all that glitters is not gold". To successfully find gold, navigate in its value, not to be confused with similar minerals, you need to know the properties of gold, where and how it occurs in nature.
Physical properties of gold
The color of gold is bright yellow if there are no impurities in it. But pure gold (and then not quite) is almost exclusively in Bank bullion. In natural gold and jewelry there are always impurities of silver, copper, etc., that is, in fact, we are always dealing with alloys of gold with other metals. The color of natural gold may depend on the size of the particles. For example, the gold of the Baley Deposit in the Chita region is described as follows: "Gold is usually found in veins in the form of tiny particles. These particles sometimes accumulate, giving loose growths and clusters visible to the naked eye. The appearance of these clusters is such that the observer who sees them for the first time does not recognize them as gold.
Gold is easily polished and has a high reflectivity. Through very thin sheets of gold, the sun's rays can perfectly pass, while their thermal part will be reflected. For this reason, thin layers of gold are used for the tinted glass of modern skyscrapers in hot climates. This saves the energy needed to keep the interior of such buildings cool throughout the hot summer months. Such thin layers of gold are also used in the protective helmet of astronauts to reflect a large stream of infrared rays in outer space.