Advertisements
Advertisements
Question
Account for the following :
Zr and Hf have almost similar atomic radii.
Solution
Due to lanthanide contraction, Zr and Hf have almost similar atomic radii. It can be explained on the basis of shielding effect. The electrons present in inner shells, shield the outer electrons from nuclear charge, making them experience a low effective nuclear charge. The shielding effect exerted by the electrons decreases in the order s > p > d > f. The f subshell poorly shields the outer electrons from nuclear attraction, which results in more attractive pull of nucleus on outer electron. In case of post lanthanide elements like Hf, 4f subshell is filled and it is not very effective at shielding the outer shell electrons. Therefore, Zr and Hf have almost similar atomic radii.
RELATED QUESTIONS
Which among the following pairs of elements is 'not' an example of chemical twins?
What are the different oxidation states exhibited by the lanthanoids?
Name the members of the lanthanoid series which exhibit +4 oxidation state and those which exhibit +2 oxidation state. Try to correlate this type of behavior with the electronic configurations of these elements.
Explain the cause of lanthanoid contraction?
General electronic configuration of actinoids is `(n-2)f^(1-14)(n - 1)d^(0-2)ns^2`.Which of the following actinoids have one electron in 6d orbital?
(i) U (Atomic no. 92)
(ii) Np (Atomic no.93)
(iii) Pu (Atomic no. 94)
(iv) Am (Atomic no. 95)
On the basis of Lanthanoid contraction, explain the following:
Stability of the complexes of lanthanoids.
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of ______.
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of _______.
Write any two consequences of Lanthanoid Contraction.
Which one of the lanthanoids given below is the most stable in divalent form?
