Question

Which group of element was missing from Mendeleev's original periodic table?

Answer 1

18th  group of elements was missing from mendeleev's original periodic  table because they are virtually imperceptible  due to the fact that they won't  react with any other elements

Answer 2

Answer:

18th group elements were missing from Mendeleev's original periodic table.

Explanation:

Mendeleev's periodic table was based on atomic mass of elements. Here, the elements are arranged in the increasing order of atomic masses.

The group 18th of periodic table which is composed of Noble gases mainly was missing from the Mendeleev's periodic table. The reason for this is that Noble gases are least reactive, therefore, it was difficult to predict such elements which do not react with other elements.

Hence, it was not part of that table.