Question

मेंडेलीवहचया आवर्त सारणीतील दोष कोणते,,? ​

Answer 1

Answer:

1) Isotopes discoverd long time after Mendeleev's put forth the periodic table.They have same chemical properties but different atomic mases.

2) The elements cobalt(Co) and nickel(Ni) have same whole number atomic mass. As a remit there was an ambiguity regarding their sequence in Mendeleev's periodic table.

3) Position of Hydrogen: Hydrogen shows similarity with Haloges (group VII) .It is difficult to decide whether it is in the group of alkali metals (group I) or in the group of halogens (group VII).