Mendeleev predicts the existence of an element that is heavier than titanium and zirconium.

Dmitri Mendeleev predicted the discovery of atomic number 72. Ironically enough he dies at the age of 72 several years before Hafnium is discovered and added to the periodic table of elements as 72HF.

Dmitri Mendeleev

Dmitri Mendeleev was born in Siberia in 1834. His widowed mother ran a glass factory and the young Dmitri hung out with the factory chemist.

Mendeleev's philosophy of life as a youth can likely be summed up by this Mendeleev quote.

" We could live at the present day without a Plato, but a double number of Newton's is required to discover the secrets of nature, and to bring life into harmony with the laws of nature. "

He moves to Moscow with his mother Maria some time after the glass factory burns to the ground.  When he failed to enter the University in Moscow he moved on the St. Petersburg where he began to study to become a science teacher. Maria died shortly thereafter and Dmitri develops a serious illness that keeps him bedridden for a year or so. But he keeps to his studies from home and graduates first in his class. His masters thesis was called " Research and Theories of Substances due to the Heat. ".

He teaches science for a few years and pursues his studies of the periodic table and chemical technology. Another passion of his is the workings of  Russia's industries. In 1859 he is contracted by the Minister of Public Instruction to go on a sabbattical journey abroad and to return with greater knowledge of how others are doing in the fields of science and technology. In Paris, Mendeleev studies gases with Renault. In Germany he studies spectroscopy with Kirchoff.

Back in St. Petersburg he becomes Professor of Chemistry at the Technological Institute and later he held the same title at the University. He earns a Doctorate degree after writing " On the Combinations of Water and Alcohol ". All the while Dr. Dmitri Mendeleev is contemplating the merits of the periodic charts.

His scientist and educator life was full of scholarly accomplishments yet is family life seemed to suffer a bit from his passions.

In 1869 he was ready to present his observations and descriptions of 60 elements to the Russian Chemical Society. The paper he'd prepared for this day was called " The Dependence between the Properties of the Atomic Weights and the Atomic Elements.". It was in this paper that he expressed, " We must expect the discovery of many yet unknown elements - for example - elements analogous to aluminium and silicon - whose atomic weight would be betwen 65 and 75. ".

A few years later Mendeleev's prediction begin to came to pass and add substanstially to his professional credential.

In 1923 Hafnium - atomic element 72 is discovered.

Dmitri Mendeleev stayed in St. Petersburg after retiring from the University of St. Petersburg.

He passed away at the age of 72 in 1907.     

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72 seems like a very average age to die.
The average heartbeat of an adult at rest is 72 beats per minute.
The amount of water in the body is 72 parts per 100.
A generation in ancient Egypt was 72 years.
......72 strange things ???????????????????????