Lithium is a chemical element with symbol Li and atomic number 3. Lithium is located in the periodic table among the elements
of the second period and in the first group as the first alkali metals. Pure lithium is a silvery-white metal, which is soft and light,
as it is the least dense metal among the solid chemical elements under standard conditions of pressure and temperature.
As a result of the great chemical activity of the element lithium, it is not found in nature in its free form, so it is usually stored in
a medium of mineral oil. At room temperature and in a completely dry medium, lithium remains for a relatively long time before
it turns into lithium nitride as a result of its interaction with air nitrogen. In the wet medium, a gray layer of lithium hydroxide is
formed on the surface of pure lithium.