Dreams are able to change reality, if they are implemented. Sometimes it is in them that people find answers to their questions.
Sometimes even the dreams of a scientist become a new stage of evolution.
So it was with Mendeleev and his periodic law.
How it all began
Refuting the established history thatA brilliant discovery in the field of chemistry was just a nightmare, it must be said that many scientists before Mendeleev made attempts to create a chemical system. Its foundations were laid by the German scientist I.V. Döbereiner, the Frenchman A. de Chancourtua and some others.
DI himself. Mendeleev spent an incredible amount of experiments and spent about twenty years of his life in search of truth. He formed the basic values and functions of the elements, as well as their properties, but only the information did not fit into something less structured. And when, after another sleepless night, he decided to rest for a couple of hours, the brain gave out what Mendeleev wanted for so many years.
This is how the periodic table appeared at the disposal of chemists in 1869, and only in 1871 the law itself was formulated, which allowed not only chemistry, but also many other sciences to go ahead.
The essence of the law
Russian scientist Dmitry Ivanovich MendeleevFor the first time an amazing discovery was made of the fact that an atom is not a finite unit, that it has a nucleus and protons rotating around it, as well as neutrons, that the bulk of the atom is concentrated in its core. A rule was derived on the change in the properties of all elements existing in nature and their chemical compounds, depending on how the charge of atomic nuclei varies.
The increase in nuclear charge occurs precisely whenThe transition from one chemical element of the table to the second, located in the neighborhood. The charge for 1 elementary charging unit is growing, and this is reflected in the table at the bottom of each element, designated as an atomic number. This means that the number of protons in the nucleus is equal numerically to the number of electrons of that neutral atom that corresponds to the nucleus.
It is the outer shells, consisting ofElectrons, the properties of any chemical elements are determined. These shells can change only periodically, and these changes directly depend on the increase or decrease in the charges of the nucleus itself located in the atom, and this, and not the atomic mass of the elements, underlies the periodic law.
Why is it so important?
Due to the periodic law appearedThe ability to predict the behavior of certain chemical elements in various reactions. It was also determined that there are still connections not discovered by science. Only after centuries the table was completely filled.