Question

The ideal gases were in ____  group of Mendeleev’s periodic table.

(a) 3^rd

(b) 4^th

(c) 1^st

(d) 2^nd

The question was asked in an interview.

Origin of the question is Genesis of Periodic Classification topic in division Classification of Elements and Periodicity in Properties of Chemistry – Class 11

Answer 1

Right option is (c) 1^st

To explain I would say: Dmitri Mendeleev classified elements based on chemical and physical properties in ascending order of their atomic weights. Noble gases were placed in the first group of Mendeleev’s periodic table.