Not to miss out, element 102, Nobelium, No, is named in honor of Alfred Nobel, who set aside his vast fortune to establish Nobel Prizes. Mendeleev never received a Nobel Prize for his work, but element 101 was named Mendelevium, Md, after him. For instance they discovered phosphorus when they isolated it from urine. Over time these gaps have gradually been filled in as scientists unearthed new elements. Not only did Mendeleev arrange the elements in the correct way, but he also had the foresight to leave gaps for undiscovered elements. At that time, he had only 50 elements to arrange. He wrote the properties of the elements on pieces of card and rearranged them until he realised that, by putting them in order of increasing atomic weight, certain properties of elements regularly occurred. The elements in group 1 are known as the alkali metals, those in group 2. Groups are numbered 118 from left to right. Elements can be classified as metals, metalloids, and nonmetals, or as a main-group elements, transition metals, and inner transition metals. Then in 1869, a Russian scientist called Dmitri Mendeleev produced one of the first practical periodic tables. Elements in the same group of the periodic table have similar chemical properties. Several other attempts were made to group elements together over the coming decades. (credit a: modification of work by Serge Lachinov credit b: modification of work by Den fjttrade ankan/Wikimedia Commons) By the twentieth century, it became apparent that the periodic relationship involved atomic numbers. The earliest attempt to classify the elements was in 1789, when Antoine Lavoisier grouped the elements based on their properties into gases, non-metals, metals and earths. Figure 2.25 (a) Dimitri Mendeleev is widely credited with creating (b) the first periodic table of the elements. The discovery of other elements followed regularly and soon it became necessary to arrange them in some sort of order. However, the first scientific discovery of an element occurred in 1649 when Hennig Brand discovered phosphorous. For example, many elements appear shiny, are malleable (able to be deformed without breaking) and ductile (can be drawn. Many elements differ dramatically in their chemical and physical properties, but some elements are similar in their behaviors. Copper has been used by humans for as much as 7000 years and elements such as gold, silver, tin, lead and mercury have been known for many thousands of years. 2: Elements in the periodic table are organized according to their properties.
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