(In the modern periodic table, a group or family corresponds to one vertical column. The periodic table allows chemists a shortcut by arranging typical elements according to their properties and putting the others into groups or families with similar chemical characteristics. Were it not for the simplification provided by this chart, students of chemistry would need to learn the properties of all 118 known elements. The term “periodic” is based on the discovery that elements show patterns in their chemical properties at certain regular intervals. Mendeleev left spaces for elements he expected to be discovered, and today’s periodic table contains 118 elements, starting with hydrogen and ending with oganesson, a chemical element first synthesized in 2002 at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, by a team of Russian and American scientists. Its story is over 200 years old, and throughout its history, it has been a subject for debate, dispute and alteration.Īttempts to classify elements and group them in ways that explained their behavior date back to the 1700s, but the first actual periodic table is generally credited to Dmitri Ivanovich Mendeleev, a Russian chemist who in 1869 arranged 63 known elements according to their increasing atomic weight. Go into any scientist’s office or lecture hall anywhere in the world and you are likely to see one. Also note the highlighted column labels elements in columns 1A-8A are referred to as Main Group Elements, those in 1B-8B. Elements here are color coded: metallic elements are blue, nonmetals are pink, and metalloids are purple. There is no more enduring reflection of science than the Periodic Table of Chemical Elements, which sheds light not only on the essence of chemistry but physics and biology as well. Figure 4-2: The 'twin-towered' edifice we know as the Periodic Table of the Elements embeds a wealth of information.
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