Table 1 was used in schools right from 1869 (year of publication), being introduced itself Mendeele

Periodic table of chemical elements was invented gold rate by Russian chemist Dmitri Mendeleev in 1869 At completion, Mendeleev left spaces, suspecting that they would be discovered and other new elements in nature, gold rate as confirmed later.
Table 1 was used in schools right from 1869 (year of publication), being introduced itself Mendeelev his students at the University of St. Petersburg. 2 In the original table, gold rate Mendeleev did not describe any of the 63 elements known at that time. Instead, each item has added a set of data on atomic weight. 3 In order to know the weight of the atom, the researchers found in the electrolytic solution. In a solution passed electric current, so that the solution has a formed separately atoms (for water electrolysis to obtain hydrogen and oxygen). Responding to the polarity of the battery, each atom has migrated in separate containers, where it was weighed, so researchers can determine their relative weight. 4 Although left gaps in the table, Mendeleev described weight and possible chemical properties of the elements that had to be discovered. But in 1894, when it was discovered argon, had no place in the table where match. When Mendeleev denied its existence. Just as he did with the other noble gases their discovery (helium, neon, krypton, xenon and radon). 5 In 1902 realizes the mistake, neanticipând discovery of inert elements such as noble gases, which have their own group of 8 in the table. 6 Now the items are sorted in the table according to the number of protons or "atomic number". This configuration causes the element layer structure and the chemical properties of the electrons. 7 noble gases (rare gases are also called) are all occupied electron layers because of this they are reactive, inert. Radon is radioactive and is only of noble gazelles is not naturally occurring in the atmosphere. 8 interactive periodic table! You get a modern periodic gold rate table remove columns in its midst complicated then it accommodate the length of the middle group of four secondary. Overlapping groups are placing additional electrons. The overlapping of these elements gold rate react with each other naturally. For example, sodium chloride will overlap, and such as NaCl or salt form. 9 carbon, an atom of group 4, is one of the most common elements. Due to its flexible links is he who holds the key molecular life. Up to 50% of us can be carbon, and nature is found in various forms due to its links: gold rate gas, crystalline gold rate forms (graphite, diamond). Fullerenes (C60) is also a class of carbon gold rate compounds. 10 elements with an atomic number greater than 92 is not normally found in nature. They can be produced by bombarding an atom with another atom or atom sides. The newest members in the system are the 114 and 116 (no name yet). 116 appears and disappears in a few milliseconds. Anyway discoveries gold rate will stop at 137, researchers saying it would limit protons. So an element 138 would be very unlikely.
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