Advertisements
Advertisements
Question
What is lanthanoid contraction? Write the.............
Advertisements
Solution
The regular decrease in atomic and ionic radii from lanthanum to lutetium with increasing atomic number is called lanthanoid contraction.
Consequences :
The net result of the lanthanoid contraction is that the second and third d-series exhibit similar radii
Zr =160 pm
and Hf = 159pm
They have very similar physical and chemical properties.
APPEARS IN
RELATED QUESTIONS
Account for the following :
Zr and Hf have almost similar atomic radii.
The chemistry of the actinoid elements is not so smooth as that of the Lanthanoids. Justify this statement by giving some examples from the oxidation state of these elements.
Account for the following:
Zn, Cd and Hg are soft metals.
Gadolinium belongs to 4f series. It’s atomic number is 64. Which of the following is the correct electronic configuration of gadolinium?
Although +3 is the characteristic oxidation state for lanthanoids but cerium also shows +4 oxidation state because:
(i) it has variable ionisation enthalpy
(ii) it has a tendency to attain noble gas configuration
(iii) it has a tendency to attain f 0 configuration
(iv) it resembles Pb4+
On the basis of Lanthanoid contraction, explain the following:
Nature of bonding in \[\ce{La2O3}\] and \[\ce{Lu2O3}\] .
On the basis of Lanthanoid contraction, explain the following:
Stability of the complexes of lanthanoids.
On the basis of Lanthanoid contraction, explain the following:
Radii of 4d and 5d block elements.
On the basis of Lanthanoid contraction, explain the following:
Trends in acidic character of lanthanoid oxides.
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of ______.
