At that time, all chemists of the world tried to structure all known elements into a single concept. Who discovered the periodic table of chemical elements?īy the middle of the 19th century, scientists had already discovered 63 elements from the modern periodic table. In the table, periods are rows, and groups are columns. Also, the elements in the table are ordered according to the electronic configuration of the atoms and the repeated chemical properties. It is always positive.įor example, hydrogen has a nucleus charge of +1, calcium will have +20, and so on. And the nuclear charge, in turn, is the number of a chemical element in the table. If you look closely at the structure of the table, you will notice a periodic change in the properties of the elements with increasing nuclear charge. Why is it called “periodic”? The answer to this question is straightforward. Why do we call the table “periodic”?īut let’s get back to the periodic table of chemical elements. 94 of them are found in nature (some only in trace amounts), and the others 24 are artificially synthesized.Ītoms of various elements interact to form compounds in different combinations and form a huge amount of natural and synthetic substances. To date, 118 chemical elements are known. For example, Nitrogen is indicated as “N”, Aluminum as “Al”, Helium as “He”, Iodine as “I”. As a rule, the first letters of its Latin name are used. The symbol for a chemical element consists of one or two letters. Each chemical element has a name and is indicated by a symbol or chemical sign. Atoms of different chemical elements differ in mass, size, structure, and properties. What is a chemical element?Ī chemical element is a specific type of atom with an individual set of protons and neutrons in the nucleus and electrons that revolve around the nucleus. In order to realize the structure of the periodic table of chemical elements, you must first understand what a chemical element is.

Nowadays, the formulation of this law is as follows: the elements of the table have changes in their properties in accordance with certain periods. This is a clear example of the periodic law, which was formulated by Dmitry Ivanovich Mendeleev in 1869. The Periodic table of chemical elements is a structured table with a sequence of chemical elements arranged in strict order with the periodic law of chemistry. What is the Periodic table of chemical elements?

Printable periodic table of elements