How did mendeleev come up with the first periodic table of elements
Dmitri Mendeleev, a Russian chemist, created the first periodic table of elements in 1869. He organized the elements based on their atomic weights and properties. Mendeleev noticed that certain elements had similar properties, and he arranged them in a logical and orderly manner.
1. Collecting data: Mendeleev collected data on all known elements at the time, including their atomic weight, chemical properties, and known compounds.
2. Sorting elements by weight: He arranged the elements in order of increasing atomic weight, placing elements with similar properties in the same vertical columns.
3. Pattern recognition: Mendeleev observed that when the elements were arranged in this manner, certain patterns emerged. Elements in the same column had similar properties and reacted similarly with other elements.
4. Missing elements: Mendeleev left gaps in his table for elements that were yet to be discovered. He predicted the properties of these missing elements based on their position in the table and the patterns he observed.
5. Correcting inaccuracies: Mendeleev made adjustments to the order of some elements based on their properties, even if their atomic weight did not fit perfectly into the pattern.
6. Predicting new elements: One of the most significant contributions of Mendeleev's periodic table was his ability to predict the existence and properties of elements that were not yet discovered. When these elements were later discovered and found to match Mendeleev's predictions, his periodic table gained credibility.
Overall, Mendeleev's periodic table provided a systematic and organized way of understanding and classifying the elements based on their properties, which laid the foundation for our modern periodic table.