What is the evolution of the atomic structure?

Atomic structure. A model is a scientist's image depiction of the structure of an atom based on his own understanding. One model represents a stage in human understanding of the structure of the atom.

The history of mankind's understanding of the atom is long and endless. The following models of atomic structure concisely and vividly illustrate the evolution of mankind's understanding of atomic structure.

Dalton. Atomic Model (1803): Atoms are the basic particles that make up matter, and they are solid, indivisible solid spheres.

Thomson. Atomic model (1904): An atom is an evenly distributed particle with a positive charge, which is embedded with many electrons, neutralizing the positive charge and thus forming a neutral atom.

Rutherford atomic model (1911): In the center of the atom there is a positively charged nucleus, its mass is almost equal to the entire mass of the atom, and the electrons orbit around it in different orbits, just like a planet orbits the sun.

Bohr atomic model (1913): electrons in the nucleus.

A certain orbit in outer space orbits the nucleus in a high-speed circular motion.

The Electron Cloud Model (1927–1935): A Modern Theory of the Structure of Matter.

Scientists are now able to use electron microscopy and scanning tunneling microscopy.

Take a ** that represents an image of an atom. With the development of modern science and technology, the process of human understanding of atoms will continue to deepen.

Since the British chemist and physicist Dalton (1766-1844) (pictured right) founded the theory of the atom, it has long been believed that atoms are small, indivisible solid spheres with no more tricks in them.

Since the discovery of cathode rays by German scientist Hitoff in 1869, a large number of scientists such as Crookes, Hertz, Lerner, and Thomson have studied cathode rays for more than 20 years.

Eventually, Joseph John Thomson discovered the existence of electrons. Normally, atoms are not charged, since negative electrons can run out of atoms that are 1700 times smaller than their mass, which indicates that there is a structure inside the atom, and it also means that there are positively charged things in the atom, and they should be neutralized with the negative charge carried by the electrons, so that the atom is neutral.

In 1902, the German physicist Philippe Edward Anton Lenard (1862-1947) proposed a neutral particle dynamical model in a row. Lernard's early observations showed that cathode rays could travel through the aluminum window inside the vacuum tube to the outside of the tube. Based on this observation, he proved in 1903 that high-speed cathode rays can pass through thousands of atoms by absorption experiments.

According to the semi-materialist view that prevailed at the time, most of the volume of the atom was empty space, and the rigid matter was only about 10 of its total (i.e., 1/100,000). Renard envisions "rigid matter" as a composite of several positive and negative charges scattered in the internal space of atoms.

Evolution of models of atomic structure.

At the beginning of the century, the British scientist Dalton proposed the modern atomic theory, which he believed that the atom was a tiny, unleaded solid sphere that could be divided. Tachibana Zen.

In the year, the British scientist Thomson discovered the electron.

The atomic structure model of "raisin noodle round dust bag" was proposed.

The British physicist Rutherford proposed a model of atomic structure with a nucleus.

In the year of the Danish physicist Bohr, he introduced the view of quantum theory and proposed a model of the atomic structure of electrons moving in a certain orbit.

6. Schrödinger, an Austrian physicist, proposed an electron cloud model.

The relationship between the Troopers can be illustrated by the following expression:

Neutron + proton = nucleus.

Nucleus + electron = atom.

The density of the nucleus is extremely high, and the electron mass is extremely light, which is generally negligible.

The volume of an atom is determined by the number of outer electron layers, and the mass is determined by the number of neutrons and protons in the nucleus.

Atoms are composed of a positively charged nucleus in the center and negatively charged electrons outside the nucleus (antimatter is the opposite), and the nucleus is composed of two particles, protons and neutrons, and the electrons move at high speed in a large space outside the nucleus.

Atoms are very small, in the case of the carbon (c) atom, which has a diameter of about 140pm (picometers), but is usually recorded in radius, in the case of millimeters (mm), the diameter is, is made up of the nucleus located in the center of the atom and some tiny electrons that move around the center of the nucleus, just like the sun or the planets of the system orbit around the sun. And the atom is the same as any black particle in the universe. Recent studies of the nucleus suggest that protons or neutrons in the nucleus may be a spherical vibrational energy layer composed of two balanced forces, internal and external.

Using this principle, a variety of relatively stable nuclei can be constructed from different sizes of energy stack layers.

A correct understanding of the composition of atoms:

1) The nucleus is located in the center of the atom, most of which are composed of protons and medium (there is a hydrogen atom that only contains 1 proton in the nucleus, no neutron), the body is small, the density is extremely large, almost the entire mass of the atom is concentrated, and the mass of electrons outside the nucleus is very small and negligible.

2) Each atom has only one nucleus, and the number of nuclear charges (the number of protons in the nucleus) determines the original type.

3) In atoms: the number of nuclear charges, the number of protons, the number of electrons outside the nucleus.

4) The number of protons in the nucleus is not necessarily equal to the number of dry neutrons, such as in the sodium atom, the number of protons is 11 and the number of neutrons is 12.

5) Not all atoms have neutrons, for example, there is a hydrogen atom that does not have neutrons.

6) In atoms, although there are charged particles in the atoms, the atoms as a whole are not electrically charged, because the number of charges carried by protons (nuclei is noisy) and the electrons are opposite.