Question

List the anomalies of mendeleev's periodic table which were renamed by modern periodic law

Answer 1

- He couldn't explain the position of hydrogen
- He couldn't explain the position of isotopes of some elements
 Since his table was based on the virtue of atomic mass,
- He couldn't explain why some elements with more atomic mass were placed before the ones with less mass

Answer 2

"The periodicity of Mendeleev was characterized on the basis of atomic weights.

1.  Certain elements of higher mass were placed "before" the elements of relatively lower mass. Co and Ni, for instance.

2.  Dissimilar elements were placed together in the form of group subgroups. For example, 1a group consisted of alkali metals and 1b consisted of coinage metals.

3.  Hydrogen was placed in the first group although hydrogen had intermediate properties between the seventh (halogens) and the first (alkali) group."