The structure of the atomic nucleus: the history of study and modern characteristics

The structure of the atomic nucleus is one of the most fundamental questions of modern science. Constantly produced experiments in this field allowed scientists to determine not only with a high degree of accuracy what an atom is from itself, but also actively use the knowledge gained in various industries and in the creation of the newest weapons.

The question of the structure of everything on the planet has interested scientists since time immemorial. So, in ancient Greece, some scientists believed that in its structure matter is one and indivisible, and their opponents insisted that matter is divisible and consists of the smallest particles - atoms, so the properties of different objects so differ from each other.

A breakthrough in the study of the structure of molecules occurred in the XVIII century, when in the works of M.V. Lomonosov, L. Lavoisier, D. Dalton, A. Avogadro laid the foundations of the atomic-molecular theory, according to which everything in nature consists of molecules, and those in turn are made up of indivisible particles-atoms whose interaction with each other determines Basic properties of these or other substances.

A new stage in the study of the structure of molecules and atoms began at the end of the 19th century, when E. Rutherford and several other scientists made discoveries, as a result of which the structure of the atom and the atomic nucleus appeared in a completely new light. So, it turned out that the atom is not at all an indivisible particle, on the contrary, it consists of even smaller components - the nucleus and electrons that move around it in intricate orbits. The general neutrality of the atom led to the conclusion that electrons having a negative charge should be balanced by elements with a positive charge. As it turned out later, such elements do exist: they are called ɑ-particles, or protons.

Modern scientific knowledge allows us to assert that the structure of the atomic nucleus is much more complicated than it seemed even a hundred years ago. So, for today it is known that the nucleus of an atom includes not only protons, but also particles that do not possess a charge-neutrons. Together, protons with neutrons are called nucleons. Since the neutron mass is only 0.14% higher than the proton mass, it is usually neglected in calculations.

The size of the core is between 10-12 and 10-13 cm. In spite of the fact that more than 95% of the atomic mass is concentrated in the nucleus, the size of the atom itself is one hundred thousand times larger than the size of the nucleus.

The main quantitative characteristics that characterize the structure of the atomic nucleus can be extracted from the periodic table of D.I. Mendeleev University. As is known, the number of protons in the nucleus is equal to the sum of the electrons rotating around it and corresponds to the ordinal number in the element table. In order to know the number of neutrons, it is necessary to subtract the serial number from the total mass of the element and round it to an integer. Substances in which the number of protons coincide, and the number of neutrons is different, are called isotopes.

One of the most important questions asked by scientists who studied the structure of the nucleus was the question of the forces holding protons, because, having the same charge, they should be repulsed. As studies have shown, the distances between protons in the nucleus are so small that repulsion between them simply does not arise. Moreover, the bions that are located between the protons, contribute to close interaction and constant attraction of the latter to each other.

The structure of the atomic nucleus still contains many mysteries. Their solution not only helps humanity to better understand the structure of the surrounding world, but also to make a qualitative breakthrough in science and technology.