Question

11.State Modern Periodic Law. Name the two elements
of first period​

Answer 1

Answer:

According to modern periodic law : The properties of elements are a periodic function of their atomic numbers. The two elements of first period are Hydrogen (H) and Helium (He).

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Answer 2

Answer:

Modern periodic law states that physical and chemical properties of the elements are periodic function of the atomic numbers i.e.if the elements are arranged in order of their increasing atomic numbers, the elements with similar properties are repeated after certain regular intervals.

Two elements are:- Hydrogen(H) and Helium(He). Two Compounds:- H2O(Water) and SO2(Sulphur Dioxide).

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