Johann Dobereiner (jan 1, 1829 – jan 1, 1829)

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Content & Description : John Dobereiner, a German chemist, discovered the concept of triads in 1829. He noticed that certain groups of three elements, when arranged in order of increasing atomic weight, exhibited similar chemical properties. These groups he termed "triads." Dobereiner's triads were based on the observation that the atomic weight of the middle element in a triad was often approximately equal to the average of the atomic weights of the other two elements. Additionally, the middle element often had properties that were intermediate between those of the lighter and heavier elements in the triad.


Importance: Dobereiner's triads were a significant step towards understanding the relationships between elements and their properties. They provided a foundation for future chemists, including Dmitri Mendeleev, who would later develop the periodic table. The concept of triads helped to establish the idea that elements could be grouped based on their shared characteristics, a principle that remains fundamental to our understanding of chemistry today.


Resource: https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/06%3A_The_Periodic_Table/6.01%3A_Early_History_of_the_Periodic_Table#:~:text=In%201829%2C%20a%20German%20chemist,elements%20into%20groups%20called%20triads.

https://www.simply.science/images/content/chemistry/structure_of_matter/dev_of_periodic_table/conceptmap/Dobereiner_triads.html

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