At present, it is quite difficult to name a metal that could compete with aluminum in terms of use. It is used both in consumer goods and in high-tech devices: it makes no sense to list them completely due to widespread distribution. Why is aluminum so remarkable?
First of all, it is one of the most common metals in the earth's crust, and among other elements it occupies an honorable third place (after silicon and oxygen). However, surprisingly, until the end of the 11th century it was valued on a par with gold and silver. It is noteworthy that in 1889 D. Mendeleev was presented with a scale, the containers of which were made of gold and aluminum. The reason for this lies in the fact that at that time there was no technology to produce this metal on an industrial scale. Only in 1855, an eight kilogram ingot was chemically obtained.
The technology was further improved, but its essence remained the same - chemical displacement from solutions. And only in 1886, the electrolytic method used in modern production was simultaneously proposed in America and France. Alumina is added to the molten cryolite (a rare natural mineral), a direct current is passed through the mass , and as a result, a metal crystallizes on the electrodes. The density of aluminum is only 2.7 g / cm3, which makes it one of the lightest metals (for comparison, the density of iron is much higher - 7.9 g / cm3). By the way, all metals according to their density are divided into light and heavy. Since the specific gravity of aluminum is almost three times lower than that of copper, and its electrical conductivity is only one and a half times inferior, it is easy to understand why this metal is widely used in electrical engineering.
Wires, tires and other elements of electrical installations made of aluminum are not only cheaper than those made from their direct competitor, copper, but are also lighter. The density of aluminum is quite sufficient to create durable and at the same time plastic products: kitchen utensils (plates, forks, bowls), foil rolls for household use, etc. However, since aluminum is able to easily form alloys with most other metals, it you can give the necessary properties. For example, an alloy based on aluminum and magnesium is characterized by high strength (for every 1% of magnesium there is an increase in strength by 30 MPa); mixing copper with aluminum allows one to achieve mechanical properties characteristic of some steel grades.
The density of aluminum (in pure form) is found from the tables of characteristics of metals. As already indicated, it is equal to 2.7 g / cm3. In some cases, it becomes necessary to find out the density of aluminum using formulas (for example, if the material of which the body is made is unknown). There are several ways to solve this problem, but the most accurate result is the division of body weight by the volume it occupies. If everything is clear with the mass, then the volume of an oversized product can easily be found by measuring the displaced fluid (remember Archimedes with his bath). It is clear that it is not always possible to perform direct weighing, so this method is not universal, although it is it that gives the most accurate result.
Interestingly, those who found the times of the Soviet Union remember the abundance of products from aluminum and its alloys, but now there is no trace of the former greatness, since the cost of this metal has grown significantly. Why? This is due to the fact that with the electrolytic method to obtain 1 ton of blister aluminum, it is necessary to spend about 15-17 000 kilowatt-hours of electricity (direct current). Moreover, in this case, the costs of rare cryolite are not taken into account, especially if it was synthesized artificially.