Question

How modern periodic law was different from earlier periodic laws?

Answer 1

Part 1:- What is modern periodic law:-

1. It states that the “physical and chemical properties of the elements are a periodic function of their atomic numbers.”

Part 2:- What is the earlier periodic law (Mendeleev's periodic law):-

1. It states that “the properties of the elements are a periodic function of their atomic masses.”

Part 3:- Difference between modern periodic laws and earlier periodic law:- The actual difference between these two laws is that in the modern periodic law the properties depend on the periodic function of the atomic numbers, and in the earlier periodic law the properties depend on the periodic function of the atomic masses. This is how they both are different.