Introduction Dmitri Mendeleev was born in Tobolsk (Russia) on the 8th of February 1834. After he received a scientific education in Russia and Germany, he became professor and he made scientific research in the chemistry field. He is known for […]
Dmitri Mendeleev was born in Tobolsk (Russia) on the 8th of February 1834.
After he received a scientific education in Russia and Germany, he became professor and he made scientific research in the chemistry field.
He is known for the discovery of the periodic law (which was introduced in 1869) and also for the creation of the periodic table of the elements. He died in St Petersburg (Russia), on the 2nd of February 1907.
Dmitri Mendeleev was born in the Russian part of Siberia on the 8th of February 1831, he was the last of 16 brothers. His father was professor at the university.
When his father became blind, his mother reopened their glass factory which before was closed by his dad. When Mendeleev was 13 his father died and when he was 15 the glass factory was burned down.
At 16 years old he moved to St Petersburg where he won a scholarship in the principal institute of pedagogy of the capital city, also because the director knew his father.
Here, he learned how to teach. At 20 years old he published some papers of his research. In many cases he had to work from bed due to tuberculosis.
He graduated with merit, despite his uncontrollable behavior that put him in a bad light with his professors and schoolmates.
In 1855, at 21 years old, he was called to teach science in Crimea, but soon after he went back to the capital city.
Here, he studied for a master in chemistry at the University of St Petersburg and he graduated in 1856.
Mendeleev was trained to be a teacher but also to be researcher, so he occupied the majority of his time doing both. He also received an award which permitted him to continue his chemistry researches in western Europe.
During 1856-1860, he stayed in Heidelberg (Germany) where he was lucky to work at the Heidelberg University with Robert Bunsenwho, was the one who discovered Cesium with his colleague Kirchhoff through chemistry spectroscopy.
In 1860 Mendeleev was part of the chemistry international conference in Germany for the first time. The big part of the conference was spent to talk about taking a standard unit to chemistry.
This conference was fundamental for the evolution of the periodic table. The periodic table of Mendeleev was based on the atomic mass and he observed during the conference how they produced and standardized a method to determine the masses.
He also had the occasion to learn about the Avogadro law which says: “at the same temperature and pressure, equal volumes of all gases contain the same number of molecules.”
In 1861 Mendeleev went back to St Petersburg where he taught in a technical institute. In this period, he became more passionate about chemistry.
He was worried about that Russia was underdeveloped in chemistry against Germany which was very advanced. He wanted to improve Russian chemistry books.
Working like a madman, in 61 days, the 27 years old Mendeleev, wrote all he knew in 500 pages which became part of his book called “Organic Chemistry”.
This book won the Dominov award that puts him in first place in the Russian chemistry education.
Mendeleev was a charming teacher and university professor and in 1867, when he was just 33 years old, he won general chemistry university chair at the University of St Petersburg.
In this position, he decided to do another thing to improve more chemistry in Russia, publishing in 1869 “Chemistry principles”. This book spread not only in Russia, but it was also translated in other languages like English, France and German.
At that time, chemistry was a mix of observations and discoveries. Mendeleev was sure that better basic principles could be discovered; this was his belief when in 1869, he began writing the second part of his book “Chemistry principles”.
In chemistry’s core there are its elements. Mendeleev asked his self if there was a way to order these elements following a logic.
He wrote down the names of the 65 elements known at that time in play cards, each element, its proprieties and atomic mass were written on a card.
In some way he saw that the atomic masses were important. When he allied the cards following the crescent order of mass, he noticed that a scheme came up.
Mendeleev put the elements in line following the crescent order of mass in order to make the cards with same proprieties were in a column.
A bunch of cards can be divided into four seeds (diamonds, spades, hearts, flowers). In a solitaire version, a player must produce a layout in which each seed must be ordered from the ace to the king.
This disposition it’s the model of Mendeleev periodic table. He said that in a dream he saw a table where all elements were in their position; when he woke up, he wrote down it.
He needed just two weeks to publish the relation between the proprieties and the atomic mass of the elements. The periodic table was realized in the scientific field.
Why was the periodic table a success?
With his periodic table, Mendeleev not just demonstrated how the elements could be organized, but he also used it to:
- Show that some elements had different behaviors from what he expected; so this was a sub-sequence of the incorrect mensuration of the atomic masses.
- Preview eight new elements and their proprieties
In fact chemists misused incorrectly some elements’ atomic masses. And the elements that he previewed, they were discovered and his scientific reputation grew.
In 1905 the British Royal Society gave him honor, the Copley medal and in the same year entered to be part of the Royal Swedish Academy of Sciences. The element number 101 in his honor was called Mendelevium.