Question

Write any two defects of Mendeleev's periodic table.​

Answer 1

Answer:

Following are the defects in the Mendeleev periodic table:

Anomalous Pairs. The following pairs of elements don't follow the follow Mendeleev's Principles: ...

Grouping of chemically dissimilar elements. ...

Position of Isotopes. ...

Electronic arrangement. ...

Separation of chemically similar elements. ...

The position of hydrogen.

Answer 2

Explanation:

The defects of Mendeleev's periodic table are:

1. Hydrogen was placed in the group I with alkali metals like

Li, Na etc but it could be also placed in the position of

halogens.

2. The position of isotopes should be separated according

to Mendeleev's periodic rule but they were kept within the

same group.

3. There were no suitable places for Lanthanides and

Actinides series.