100 Examples of Atoms

With the name of atom the minimum unit that forms matter and that still has the properties of the chemical element to which it belongs is known. For example: aluminum, iron, iodine. The atom is the base particle of all known matter and is present in all things: in living beings and in inanimate objects.

The atom is often characterized as a indivisible unitbut it is not because it is impossible for the atom to be divided, but in the case of being divided, it would lose the chemical properties of the chemical element to which it belongs: the atom, in reality, is made up of even smaller particles: the subatomic ones.

composition of the atom

In effect, the atom composition it includes a core made up of a nucleus containing protons and neutrons, and various shells or energy levels around this nucleus that contain the smallest subatomic particles of atoms, the electrons.

While the electrons are negatively charged, protons have the same electric charge but positive neutrons they have no charge. Rutherford proposed one of the atomic models that explains the existence of positive charges in the nucleus of the atom and negative charges located in the orbits around it. Through this model it was possible to explain (albeit with some limitations) the union of atoms to form chemical compounds.

atom properties

The atom always has some properties, which are useful for understanding how they are distributed when they form different chemical compounds. The atom always has an atomic number (represented by the letter Z) that represents the number of protons it contains in the nucleus, which is equal to the number of electrons, which are around it. It also has a mass number, represented by the letter A, which refers to the sum of protons and neutrons that the atom contains in its nucleus.

Classification of atoms

There are different classes of chemical elements. The most common classification is the one made in the periodic table of the elements, which organizes and classifies chemical elements according to their atomic number, among other properties.

All atoms with the same atomic number They belong to the same chemical element. On the other hand, atoms that have different numbers of neutrons but equal numbers of protons (atomic number) are called isotopes. For example, hydrogen has three natural isotopes that are atoms: protium ^oneH (with a proton in the nucleus and an electron in its orbit), deuterium ^twoH (with one proton and one neutron in the nucleus, and one electron in its orbit) and tritium ³H (with one proton and two neutrons in the nucleus, and one electron in its orbit). But all three isotopes belong to the same chemical element, hydrogen.

History of Atomic Theory

The atomic theorywhich includes atoms as the minimum unit of the structure of matter, has existed since Ancient Greece.

In 1803, John Dalton He proposed the atomic model that showed that the union between atoms to form chemical compounds was carried out through certain defined proportions of each one. John Thomson, for his part, determined the positive and negative charge and the conformation of the ions of both signs. The next to propose an atomic model was Rutherford, who for the first time defined the positive atomic nucleus and the orbits where the electrons are located. Bohr then proposed a model that states that electrons are not located in all orbits or energy levels, but that there are permitted and prohibited energy levels.

The models followed one another until the current studies of the Quantum theory, oriented fundamentally to the fields. Obviously, it is certain that the structure of the atomic nucleus and of the very particles that make it up is much more complicated than the traditional electronic structure of atoms.

Here is a list of examples of chemical elements in the periodic table, for which there are a certain number of atoms that constitute their isotopes: