Question

There is a close similarity in physical and
chemical properties of the 4d and 5d-series of
the transition elements, much more than
expected on the basis of usual family
relationship. ​

Answer 1

Answer:

There is a close similarity in physical and chemical properties of the 4d and 5d series of the transition elements much more than expected on the basis of usual family relationship. This is because 5d and 4d series elements have virtually the same atomic and ionic radii due to lanthanide contraction.