The smallest electrically neutral particle of a chemical element: composition, structure, properties
The whole world is around, starting from the very depths of the earth andup to outer space, consists of an infinite number of objects, each of which is material. Scientists believe that matter can not be destroyed or created, it is infinite and eternal. Movement is one of the qualities inherent in matter. This is not only the spatial displacement of the bodies themselves, but also the change in their states, properties, and so on.
Matter and its systems
Space and time are considered a form of being for matter. One of its primary properties is the ability to reflect in the minds of people.
In science today, the following levels of matter and its system are distinguished:
- elementary particles;
- bodies macroscopic;
- geological systems;
- system of galaxies;
- system of universes.
All material systems are made up of living beingssubstances, that is, different organisms, which, unlike others, are able to multiply. A kind of building element for matter are elementary particles. It can be the smallest electrically neutral particle of a chemical element, which has this or that charge.
Total elementary particles, which are discovered inCurrently, there are up to three hundred. If a particle has a charge, then there must be an antiparticle. The exception is the smallest electrically neutral particle of a chemical element.
All of them are divided into:
- hadrons that participate in all interactions, they are divided into baryons (hyperons and nucleons) and mesons;
- leptons participate in all interactions, except for the strong (among which there are electrons, muons and neutrinos).
And only photons do not belong to any of the named groups.
The division is based onfundamental interactions that are strong or weak, electromagnetic, gravitational. Strong interaction is much more electromagnetic (a hundred times). The effect is at a very small distance - 10ˉ¹⁵ meters. Of course, the weak is much less than the electromagnetic one, but it exceeds the gravitational one many times.
Structure and stability of properties
Clear distinctions, which has the smallestan electrically neutral particle of a chemical element and other elementary particles, no. For example, it is known that they have a complex structure, which includes the so-called quarks.
If we consider the properties with respect to time, then the particlesshow them stably or unstable. Among the first are photons, muon and electron neutrinos, protons with electrons and their antiparticles. Other elementary particles can decay in the period from 10³ for neutrons in a free state to 10ˉ²²-10ˉ²⁴ for those particles called resonances.
Electrons, protons and neutrons
Elementary particles that form part of physical objects are called electrons, protons and neutrons.
The former have a stable negative charge andweight 9 * 10ˉ³¹ kilograms. They are leptons, since they participate in all interactions except the strong ones. Protons also have stable properties, but their mass exceeds the electronic one 1836 times. This is a baryon from the nucleus of the light isotope of the hydrogen atom. Neutrons, as the name implies, are neutral particles with a mass higher than the proton mass. These are also baryons. They are unstable and have a lifespan of up to sixteen minutes. Protons and neutrons form the nuclei of atoms.
Composition of the atom
The smallest electrically neutral particlea chemical element is called an atom. In its center there is a nucleus, which has almost the entire mass. The nucleus is charged positively, since it has only protons and neutrons in its composition. The number of protons can be determined by the number of the element and the periodic table: their number coincides with the ordinal number.
Around the nucleus are moving electrons, the number of whichis the same as for protons. The smallest electrically neutral particle is capable of giving electrons or, conversely, attaching them. Depending on this, the atom acquires a negative or positive charge. Chemical properties are manifested in dependence on the number of electrons that can be located from the nucleus at different distances and move along different orbits, with different velocities, energies.
The electric neutral elementary particle is notcan be expressed graphically. Physicists today imagine an atom in the form of a heavy nucleus with an electronic continuous cloud around. It is impossible to determine the arrangement of electrons, since there is no corresponding equipment, and also because they exhibit simultaneously wave properties.
Thanks to quantum mechanics, it was proved thateach electric neutral elementary particle can have up to several groups of electrons that create electronic spherical shells, the maximum number of which is seven.
Moving to a deeper level, the electronemits a photon. Each electron, among other things, rotates on its axis. The property was called "spin". It is believed that this speed is constant, it can not be changed in any way.
The set of atoms
How an electrically neutral particle is constructed,is studied using the spectrum. The atom emits or absorbs light lines. This becomes possible due to the energy that takes on discrete values corresponding to atomic states and changes on quantum transitions.
The set of atoms possessing one charge becomes a chemical element. Today, 107 are known, 19 of which were originally obtained by artificial means and only then discovered in nature.
Kernels with a heavy mass are unstable, so americium and the following chemical elements are obtained only in nuclear reactions.
When one electrically neutral particlechemical element is combined with the other (the number of atoms can total up to two thousand), a molecule is formed, which is the smallest particle of a substance with all its chemical properties. But this is the topic of another article.