Analysis and Description of Some Elements of the Periodic Table

The periodic table teaches many things about elements. Basically it is used as a section delimiter for an element, and each element is placed under a specific row and column property. This includes mass, proton number, neutron and electron, period, group, valence electron and so on. Chlorine is a diatomic molecule of Cl 2. There are also 24 types of chlorine isotopes, two of which are stable isotopes. Both chlorine 35 and 37 are stable isotopes of chlorine. The emergence of chlorine is a highly toxic green / yellow gas with irritating odor at room temperature.

The number of elements in the periodic table is not the only change in the table over the past 20 years. The atomic weight of some elements on the table has also been changed. These changes were developed by the International Union of Pure and Applied Chemistry (IUPAC), an organization responsible for overseeing the official periodic table. As a result, their weights are represented as several intervals instead of a single number. Bromine had previously had an atomic weight of 79.904 in the periodic table. The current interval is 79.901 to 79.907. For magnesium, its atomic weight was 24.3050. 24.304 to 24.307 are displayed in the period table. Elemental elements, indium and mercury are expected to undergo official atomic weight changes on the periodic table in the near future.

2 History of the Periodic Table Mendeleev places the elements in the world's first periodic table, Mendeleev puts the elements in the world's first periodic table, compares the number of elements that react with each other, increases the atomic weight, I will increase it. Modern periodic table is different from Mendeleev table - he does not know that protons and electrons are different from Mendeleev table - he does not understand that protons and electrons increase the number of atoms Mass proton number proton number It is not a mass increasing atom number than an electron number electron number

Please watch the periodic table A carefully. The history of the periodic table Mendeleev arranged these elements in the world's first periodic table and Mendeleev arranged this element.

In the standard periodic table, elements are listed in descending order of atomic number Z (the number of protons in the nucleus). When a new electronic shell has its first electron, a new line (cycle) begins. Columns (groups) are determined by the electronic configuration of the atoms, and elements with the same number of electrons in a particular subshell are in the same column (eg oxygen and selenium are in the outermost p subshell, so in the same column enter). There are four electrons in the center. Elements with similar chemical properties generally belong to the same family of the periodic table, but in some aspects of the f region and d region elements of the same period tend to have similar properties. Therefore, it is relatively easy to predict the chemical nature of an element if you know the properties of the elements around the element.