At the time of Mendeleev, the number of elements known was
63
65
62
64

Academic Chemistry NCERT Class 10

Correct Answer: (a) 63

Explanation: In Mendeleev’s periodic table, elements were placed based on the atomic mass, and chemical properties. At the time of Mendeleev, the number of elements known was only 63.

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Updated on: 10-Oct-2022

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