Editing Dmitri Mendeleev

= Dmitri Mendeleev – The Father of the Periodic Table =

== Introduction ==
'''Dmitri Ivanovich Mendeleev''' (1834–1907) was a Russian chemist and inventor, best known for creating the first widely recognized version of the '''Periodic Table of Elements'''. His work laid the foundation for modern chemistry and revolutionized how scientists understand the properties and relationships of chemical elements.

== Early Life and Education ==
Dmitri Mendeleev was born on '''February 8, 1834''', in Tobolsk, Siberia, Russia. He was the youngest of 14 to 17 siblings (sources vary). After the early death of his father and a fire that destroyed the family’s glass factory, Mendeleev’s mother took him to St. Petersburg to pursue his education.

He studied at the '''Main Pedagogical Institute''' and later continued his education and research in Germany.

== Contribution to Chemistry ==

=== Development of the Periodic Table ===
In 1869, Mendeleev published his first version of the '''Periodic Table'''. Unlike previous attempts, Mendeleev:

* Arranged elements in order of **increasing atomic mass**
* Grouped elements with **similar properties** into vertical columns
* **Left gaps** for undiscovered elements and even predicted their properties

Some of the elements he predicted, such as **gallium (Ga)**, **scandium (Sc)**, and **germanium (Ge)**, were later discovered and confirmed the accuracy of his table.

=== Periodic Law ===
Mendeleev's formulation:
<blockquote>''"The properties of the elements are a periodic function of their atomic weights."''</blockquote>

This later evolved into the modern version:
<blockquote>''"The properties of elements are periodic functions of their atomic numbers."''</blockquote>

== Other Scientific Work ==
While best known for the Periodic Table, Mendeleev also:

* Worked on the theory of solutions
* Studied the nature of petroleum and advocated for its industrial use
* Developed an early version of the metric system in Russia
* Wrote a widely used chemistry textbook titled '''Principles of Chemistry'''

== Awards and Recognition ==
* Member of several international academies
* Numerous medals and honors in his lifetime
* In 1955, the element '''Mendelevium (Md)''' with atomic number 101 was named in his honor

== Legacy ==
Mendeleev's scientific foresight and his ability to predict the existence and properties of unknown elements marked a turning point in the field of chemistry. He is remembered as one of the greatest chemists of all time.

== Death ==
Dmitri Mendeleev passed away on '''February 2, 1907''', in St. Petersburg, Russia.

== See Also ==
* [[Periodic Table of Elements – A Complete Guide]]
* [[Chemical Elements – A Complete Guide]]
* [[Henry Moseley]]

== References and Further Reading ==
* [https://iupac.org/ IUPAC – International Union of Pure and Applied Chemistry]
* Biography resources from Britannica and Royal Society of Chemistry
* Mendeleev, D. ''Principles of Chemistry'' (Textbook)

== Disclaimer ==
''This article is intended for '''academic and educational purposes only'''. All historical and scientific facts have been compiled from verified public sources and should be used as a supplement to standard chemistry education and historical studies.''