Question

difference between the arrangement of elements in mediaeval period periodic table and modern Modern Periodic Table​

Answer 1

HEY MATE HERE YOUR ANSWER:

1) Mendeleev's periodic table was arranged in atomic masses. So there was no place left for isotopes.

Modern periodic table was not having this problem because elements were arranged in atomic number.

2) In Mendeleev's periodic table no fix place was given to hydrogen since it has similar properties to alkali metal and halogen metals both.

Modern periodic table solved this problem by giving a different place on top left corner.

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