When did Dmitri Mendeleev invent the periodic table, ordering the symbols of the chemical elements according to their atomic weights?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 1869.
In 1869, Dmitri Mendeleev developed the periodic table, arranging elements according to their atomic weights and noting that elements with similar properties appeared at regular intervals.
This organization not only revealed gaps for elements yet to be discovered but also established a crucial basis for the modern comprehension of chemical elements and their relationships. Mendeleev's periodic table continues to be an essential resource in the field of chemistry.