Question

Give two similarities and two differences in the elements of 3d, 4d and 5d series.

Answer 1

Similarity:

1. They are placed between s-block and p-block of the periodic table.
2. All elements are metals showing metallic characters.

Differences: 

1. In 4d and 5d series, lanthanide and actinoid contraction is observed. In 3d series atomic size changes are less marked.
2. 4d and 5d elements have high coordination numbers compared to 3d elements.