Monday, February 8, 2016

Published 1:11 PM by with 0 comment

Who was Dmitri Mendeleev and how did he construct the periodic table of elements?

You may have learned the periodic table of elements during chemistry lessons at school, but how much do you know about the man widely credited for ordering the table as we know it?
Russian chemist Dmitri Mendeleev, born February 8 1834 and honoured with a Google Doodle to celebrate what would have been his 182nd birthday, published his first version of the periodic table in 1869, years after multiple scientists had attempted to order the elements.

The reason Mendeleev's version stuck was due to his using the table as a method of predicting the existence of substances, such as gallium and germanium, that had not yet been discovered. He also incorporated more elements into the table than anyone previously.


Each element within the periodic table contains its atomic number, which is equal to the number of protons/electrons within the element, its atomic weight and its element symbol, consisting of one or two letters. Some versions of the table, as above, colour the elemental blocks depending on their type; noble gases, alkali metals, solid, liquid, gas etc. 
Mendeleev categorised the elements in order of relative atomic mass which he noticed was related to their chemical and physical properties, and was able to predict the atomic mass of the as-yet-undiscovered elements which belonged in the gaps of the table.

  • The man who brought order to the particle zoo
The chemist was born in Siberia and studied at the Main Pedagogical Institute, before writing a book on the inner workings of the spectroscope, an instrument designed for measuring light's properties across the electromagnetic spectrum.
 He later worked as a professor at both the Saint Petersburg Technological Institute and the Saint Petersburg State University. His textbook Principles of Chemistry, regarded as a milestone study, was published in two volumes in 1868 and 1860.
Mendeleev died in 1907 aged 72. Element 101,  mendelevium, is named after him.


Four new elements were added to the table last month after the International Union of Pure and Applied Chemistry officially verified the 'super-heavy' elements, numbered 113, 115, 117 and 118.
They have been given temporary working names of ununtrium, ununpentium, ununseptium, and ununoctium, though element 113 may be named japonium after being discovered by scientists at the Riken institute in Japan.
“To scientists, this is of greater value than an Olympic gold medal,” Ryoji Noyori, former Riken president and Nobel laureate in chemistry, said.



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