![]() The exciting discovery that physical and chemical characteristics of the elements are periodic functions of their atomic weight became known as the periodic law. Among heavier elements, he found that characteristics recurred every seventeen elements. He found that elements with low atomic weights had similar chemical characteristics that recurred every seven elements. By simply leaving openings for elements that he believed were undiscovered, he developed an organizational scheme that vertically grouped elements with alike properties. He realized that there was a number of unknown elements with atomic weights between elements that had already been discovered. Mendeleev noticed something that no one else had. ![]() In 1869, Russian chemist Dmitry Mendeleyev systematically arranged elements in a table according to their atomic weights. Because of this theory, Dalton created a scale of atomic weight based on the hydrogen atom. In 1803 English chemist, John Dalton, used the general scientific recognition, that elements combined with each other according to different ratios by weight, to create an atomic theory that claimed all elements were built out of variable numbers of hydrogen atoms. He then proceeded to compile a list of 33 elements, which just so happen to not actually be elements but he did spur this idea of systematizing and understanding elements. In 1789, the French chemist Antoine Laurent Lavoisier defined an element as a fundamental substance that could not be broken down by any chemical means then known. ![]() Let’s look at a short history of the Periodic Table. Through its innovative organizational layout, the table gives us concise and fundamental information not just about every single element, but also about trends that occur across all the elements. The periodic table of elements is, hands down, one of the most important tools you will use in chemistry. Hey, guys! Welcome to this Mometrix video over the periodic table. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |