Question

How many times the modern periodic table have been changed and what were he changes?

Answer 1

A huge number of changes were made to the periodic table in the early parts of the 20th century.Approximately 5-8 times but the biggest changes were two one was the mendeleev's periodic table which was bassed on atomic mass and the other was henry moseley's table which was based on the atomic number currently we are using the atomic number table by Henry Moseley.

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