Question

position of isotopes in the mendeleevs and modern periodic table

Answer 1

Hey mate here is ur ans :-)
position of isotopes cannot be justified
according to the atomic weight different isotopes of an element should be given different places but it is not done so
hope it helps u

Answer 2

the elements are arranged in increasing order of atomic mass in mendeleevs periodic table and the Morden periodic law all the isotopes of elements have the the same atomic no. so ,no matter what the mass number is. hence the different isotopes of an element do not require separate position in the periodic table