English (United Kingdom)Deutschελληνικά

(Dimitri) Mendelejew

Dimitri Mendelejew (1834- 1907)

has succeeded to tabulate the periodic system (short: PSE= periodic system of elements) which contains every chemical element. He started the system to impose beginning with the smallest to the biggest element. When there were any properties in common, he put them into groups and in the periodic system he arranged them among themselves. In the end, Mendelejew illustrated a context between atomic weight and chemical characteristics. The element 101 "Mendelevium" was called by Mendelejew.

Before we inform you about his invention - the periodic table some information about his life and his growing passion for chemistry.

Dmitri Mendelejew was born on the 8th of February 1834 in Tobolsk, Russia. His father Ivan Pavlovich Mendelejew was a teacher and his mother Maria Dmitrievna Mendeleeva worked in a glass factory. In 1847 he attended the Gymnasium in Tobolsk and he began to study in 1850 in Saint Petersburg, Russia. He had to leave the city for some years because of tuberculosis and returned 1857. Then his career began to start because he became a professor at two Universities in Saint Petersburg. During the time Saint Petersburg developed as the center of chemistry analysis – also because of Mendeleev’s enormous influence and knowledge. He was honored by several international prices. and took, for example, part in the bureau of weights and measures and supported the population to find the first oil refinery in Russia. During this exploration he got in touch with petroleum, a liquid that is able to burn.

On the 2nd February 1907 Mendelejew's died in Saint Petersburg because of influenza at the age of 72. Now you know something about his life and that he liked to explore the “world of chemistry”. So what about his invention the periodic table of the elements? He invented the first authentic table of the elements in 1869 and published it in his book “Principles of Chemistry” (1868-1870). This table structured the elements by their atomic weight. Today, the table is structured by the atomic number because the chemist Henry Moseley discovered that you can declare the atomic numbers of elements. But all in all, the basic principle was discovered by Dimitri Mendeleev.

How is the table structured? The structure of the table consists of the periods (rows) and the groups (columns). The atomic number mounts when you move across the columns and rows. If the elements are in the same row they have got something in common. If the elements are in the same column they have the same number of electrons. At the top in the right and left corner you can find Helium (He) and Hydrogen (H). These two elements are very special and unique. Hydrogen can have the electrons of two groups. Helium is only able to have two electrons outwards.

Now, I want to tell you three facts about the periodic table.

  1. Francium is a really rarely element on our planet earth.
  2. The letter “J” is the only letter that is NOT in the table.
  3. Diamonds exist of the element Carbon, atomic number 6.

Famous Chemist

Gertrude B. Elion (1918-1999)

Gertrude B. Elion was born to immigrant parents in New York city. Her father came from Lithuania and her mother from Russia. She spent her early years in Manhattan where her father had a dental practice. When her brother was born they moved to Bronx.

Read more...

Louis Lumière (1864-1948)

Nobody of us can imagine the world without movies, cinemas and actors. It is unbelievable especially for people who are living in XX century. But you have to know that it was not always like this. The possibility to go to the cinema and watch a new movie gave us Louis Lumière and his brother Auguste.

Read more...

Carl Bosch ( 1874 - 1940)

 

Carl Bosch, born in Cologne, Germany, was a prominent German industrial chemist and entrepreneur.

Read more...

John Dalton (1766- 1844)

He is a famous English naturalist and teacher. He is considered as an innovator of chemistry because of his fundamental researches. Here are some examples of his successful research: the studies about thermal expansion, formulates the "Dalton- law", preparatory work of the periodic system of elements and he discovered the "Daltonism" which means acritochromacy.

Antoine Laurant de Lavoisier (1743-1794)
In 1772 he discovered the three conditions of matters: solid, liquid and gassy which he published in "Opuscule physique et chemique" (franc., small discourse of chemistry and physics). Additionally, he gave oxygen (acid-creator) his name because he discovered while some experiments that water and air are compound substances. Meanwhile the French Revolution, Lavoisier helped in introducing the "metric system" which unifies all of units.

Read more...

Dimitri Mendelejew (1834- 1907)

has succeeded to tabulate the periodic system (short: PSE= periodic system of elements) which contains every chemical element. He started the system to impose beginning with the smallest to the biggest element. When there were any properties in common, he put them into groups and in the periodic system he arranged them among themselves. In the end, Mendelejew illustrated a context between atomic weight and chemical characteristics. The element 101 "Mendelevium" was called by Mendelejew.

Read more...

Alfred Nobel (1833- 1896)

affected by his father and his engineering works, Nobel's career begins with some smaller inventions (gas -and liquid measuring instrument, barometer or manometer) which he also patented. In May 1862, Nobel ran the first successful underwater demolition with nitroglycerin. Two years later, he invented the detonation which he has called "Nobel's patent detonator". His idea of quality manufacturing was not safe to operate because a dynamite factory exploded -and even Nobel's little brother died. But Nobel did not surrender, he went on in improving the detonations.

Ernest Rutherford (1871-1937)

since 1931 was an atomic physicist. Until he was awarded with the Nobel price in 1908, Rutherford made some discoveries of highest priority for chemists. One example could be the half life before he has been honored because of his studies about the decay of elements and the chemical composition of radioactive elements. In the year 1911, Rutherford refutes the atomic model of Joseph J. Thomson and originates the "Rutherfordium atomic model". Additionally, the first artificial nuclear reaction was also succeeded by Rutherford.