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Question:
What is the basic difference in approach between the Mendeleev’s Periodic Law and the Modern Periodic Law?

Answer:

A Russian chemist, Dmitri Mendeleev was the first to develop a periodic table and he gave a law called Mendeleev periodic law which states that the physical and chemical properties of the elements are a periodic function of their atomic masses. In his periodic table the elements are arranged in vertical rows called groups and horizontal rows known as periods.There are nine groups and seven periods. He arranged only 60 elements in periodic table.

A English physicist Moseley, in 1913 gave a modern periodic law which states that the physical and chemical properties of the elements are the periodic function of their atomic number. This law becomes the base of modern periodic law. In modern periodic table, there are 18 groups and 7 periods.

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Question:
What is the basic difference in approach between the Mendeleev’s Periodic Law and the Modern Periodic Law?

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Question:
What is the basic difference in approach between the Mendeleev’s Periodic Law and the Modern Periodic Law?