You Need To Update Your Periodic Table For 2016
The 7th row of the Periodic Table has been completed after 4 new elements have been added. The elements, 113, 115, 117 and 118, were discovered by scientists in Japan, Russia and America and are the first to be added to the table since 2011. They were verified by the International Union of Pure and Applied Chemistry just before the end of the year.
The Periodic Table of Elements
The periodic table is the most important chemistry reference there is. It arranges all the known elements in an informative left to right and top to bottom array in order of increasing atomic number (number of protons in the nucleus). Order generally coincides with increasing atomic mass.
The different rows of elements are called periods. The period number of an element signifies the highest energy level an electron in that element occupies (in the unexcited state). The number of electrons in a period increases as one traverses down the periodic table; therefore, as the energy level of the atom increases, the number of energy sub-levels per energy level increases.
Using the data in the table those that are familiar with the table can extract information concerning individual elements. For instance, a scientist can use carbon’s atomic mass to determine how many carbon atoms there are in a 1 kilogram block of carbon.
People also gain information from the table by looking at how it is put together. By examining an element’s position on the periodic table, one can infer the electron configuration. Elements that lie in the same column on the periodic table (called a “group”) have identical valance electron configurations and consequently behave in a similar fashion chemically. For instance, all the group 18 elements are inert gases.
Although precursors exist, Dmitri Mendeleev is generally credited with the publication, in 1869, of the first widely recognized periodic table. He developed his table to illustrate periodic trends in the properties of the then-known elements. Mendeleev also predicted some properties of then-unknown elements that would be expected to fill gaps in this table. Most of his predictions were proved correct when the elements in question were subsequently discovered. Mendeleev’s periodic table has since been expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behavior.