Dmitri Mendeleev and The Periodic Table

Dmitri Mendeleev

(Photo Credit: Biography)

Dmitri Ivanovich Mendeleev was a Russian chemist and inventor living in the 1800s. He is most famous in the science community for creating an early version of the Periodic Table. And today is his birthday - Dmitri Mendeleev was born on this date 185 year ago. Seen as this year happens to be the international year of the Periodic Table, I thought that I should celebrate one of the many people who helped to create what the periodic table is today.

When Dmitri had his idea for the periodic table, there were only 56 elements. There is 118 elements in total now. Then to make things even more complicated for those constructing the modern periodic table, a new element was being discovered at a rate of one a year.

There were other scientists who were trying to create an update the table. The first scientist was John Newlands who published his work in 1865. It described a Law of Octave which noted an element on its relevant atomic weight. His proposal recognised that there were going to be other elements such as Germanium. This concept was criticised and this innovation wasn't recognised by the Society of Chemists by 1887.
Another scientist was Lothar Meyer. He published a paper in 1864 which had 28 elements but no room to expand for new elements.

John Newlands' Periodic Table

(Photo Credit: Wikipedia)

Whereas Dmitri became a teacher in the year 1867 and wrote a textbook named Principal of Chemistry. It was then the chemist made his most important discovery. Dmitri classified the elements due to the chemical properties where he started to notice patterns. During all of this work on his own periodic table, Dmitri Mendeleev was unaware of the work that was going on from John Newlands and Lothar Meyers. It was only on the day of the 6th of March 1869 when Dimitri Mendeleev made a formal presentation to the Russian Chemistry Society. The presentation was titled - The Dependence between the Properties of the Atomic Weights of the Elements.
And these are some of the points of the presentation that were said;

• Elements of similar chemical properties either has similar atomic weight or the atomic weight increases regularly
• Elements and their arrangement into groups relates to their valence (the measurement of element's combined power over others) which is apparent across the group.
• Elements that are most widely defused have the smallest weight

Mendeleev published his version of the periodic table of the elements along with any new elements within a Russian journal. Meyer then published a periodic table within a German paper which was virtually similar only month after the Russian journal publication.

And let just say, Dmitri was real good with predicting new elements. He predicted the finding as well as the properties of what would become Germanium, Gallium and Scandium. Though Mendeleev was wrong about the atomic weight of the element tellurium. It was predicted as anywhere in between 123 or 126 and was found as 127.6. But, everyone can't be 100% right. 

Dmitri Mendeleev's Periodic Table

(Photo Credit: Wikipedia)

The periodic table wasn't the only thing which Dmitri Mendeleev dedicated his life too. The chemist has also published 400 books and articles which are held at The Dmitri Mendeleev's Museum and Archives located at St. Petersburg State University. 

But, chemistry was really Dmitri Mendeleev's topic. In his time, the chemist wrote about and formulised Boyle's Law. It was just his periodic table work that is the most remembered.