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Periodic Law

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What is Periodic Law?

The periodic law states that the physical and chemical properties of the elements are periodic functions of their atomic numbers; when elements are arranged in order of increasing atomic number, similar properties recur at regular intervals. Originally formulated by Mendeleev (using atomic mass) and refined by Moseley (using atomic number), this law led to the modern periodic table. Periodicity arises from the regular filling of electron shells and subshells as atomic number increases.

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Term Periodic Law

Frequently Asked Questions

The periodic law states that the physical and chemical properties of the elements are periodic functions of their atomic numbers; when elements are arranged in order of increasing atomic number, similar properties recur at regular intervals. Originally formulated by Mendeleev (using atomic mass) and refined by Moseley (using atomic number), this law led to the modern periodic table. Periodicity arises from the regular filling of electron shells and subshells as atomic number increases.

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