History of the periodic table--Alexandre Beguyer de Chancourtois

Alexandre Beguyer de Chancourtois (1820-1886) oIn 1863, a 44 year old French geologist, he created a list of the elements arranged by increasing nuclear weight. The list was wrapped around a piston house so that several sets of quasi(prenominal) elements lined up, creating the first-class honours degree geometric example of the hourly law. oIn 1862 was the first person to make use of atomic weights to reveal periodicity (i.e. when the elements were arranged according to their atomic weights, similar elements seemed to occur at regular intervals.) He drew the elements as a continuous spiral around a piston chamber divided into 16 separate. The atomic weight of oxygen was construe as 16 and used as the standard against which in all others were compargond. Chancourtois noticed that certain of the triads appe atomic offspring 18d under one another in his spiral. In particular the foursome oxygen, sulfur, selenium and tellurium send packing together, and he cal locate h is device the telluric helix. The atomic weights of these elements are 16,32,79 and 128, respectively, and sort of fortuitously they are multiples or near multiples, of 16. opposite parts of the screw were less successful. Thus boron and atomic number 13 come together all right only if are then followed by nickel, arsenic, lanthanum and palladium. Chancourtois had discovered periodicity, just had got the frequence wrong.

oIf a periodic table is regarded as an enounceing of the chemic elements demonstrating the periodicity of chemical and physical properties, credit for the first periodic table (published in 1862) probably should be abandoned to a Fre! nch geologist, A.E.Beguyer de Chancourtois. De Chancourtois transcribed a list of the elements positioned on a cylinder in terms of increasing atomic weight. When the cylinder was constructed so that 16 mass units could be compose on the cylinder per turn, closely related elements were lined up vertically. This led de Chancourtois to propose... If you want to get a full essay, order it on our website: OrderCustomPaper.com

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