Prvky.com Website Review

displays CHEMICAL ELEMENTS and their clas*ification in periodicals. PERIODICAL TABLE is divided into horizontal rows and vertical columns. Horizontal rows of the periodic table are called PERIODS. The individual chemical elements are ranked in ascending order according to the proton number in the period of the table. The period number indicates the principal quantum number of the valency orbits of the non-transitional elements. The principal quantum number n takes values ​​1-7 and determines the energy level at which the electron is located, thus expressing the energy of the electron in the shell of the atom. Vertical columns of the periodic table are GROUPs of elements that as*ociate elements of similar properties. The chemical elements in the same group have the same number of valence electrons. The number of the group indicates the number of valence electrons of non-transitional elements and at the same time states that the Russian scientist Dmitry Ivanovich Mendeleyev formulated in 1869, in 1869, the validity of Mendeleyev's periodic law was confirmed in 1875 by the discovery of an unknown element - gallia, which had the properties predicted by Mendeley . Since then Mendeleyev's periodical law, in a slightly altered form, has become one of the pillars of modern chemistry. Mendeleyev's periodic table in graphical form expresses the periodic law. A good understanding of the periodic law and the system of the periodic table, especially the rules arising from the location of individual chemical elements in the periodic system, is a basic prerequisite for success in the study of element chemistry. The location of the chemical element in the periodic system is also an important factor for the occurrence of elements in the Earth's crust. The Periodic Table of Elements on WWW.PRVKY.COM is fully interactive. Clicking on the chemical tag of any element in the table displays a page describing the selected chemical and physical properties of the chemical element. The individual elements show their chemical mark, Czech, Latin and English name, proton number, relative atomic