Multiple choice

The existence of which of the following became the reason for the failure of Mendeleev's periodic law?

  1. Alkali metals

  2. Alkaline earth metals

  3. Halogens

  4. Isotopes
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Since Mendeleev’s periodic law was based on atomic masses of the elements, the isotopes should have been  placed in different slots despite the fact that they represent the same element. This was one of the major disadvantage of Mendeleev’s periodic law.

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