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प्रश्न
On the basis of Lanthanoid contraction, explain the following:
Radii of 4d and 5d block elements.
उत्तर
As an effect of lanthanide contraction, zirconium and hafnium have similar radius of 160 pm and 159 pm respectively. Due to this similarity in their size, they show similar physical and chemical properties. Lanthanoid contraction: Because the elements in Row 3 have 4f electrons. These electrons do not shield good, causing a greater nuclear charge. This greater nuclear charge has a greater pull on the electrons and result in the decrease in their size and atomic radii.
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संबंधित प्रश्न
Define lanthanoid contraction.
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.
Write the different oxidation states of iron
Which of the following lanthanoids show +2 oxidation state besides the characteristic oxidation state +3 of lanthanoids?
(i) \[\ce{Ce}\]
(ii) \[\ce{Eu}\]
(iii) \[\ce{Yb}\]
(iv) \[\ce{Ho}\]
Although Zr belongs to 4d and Hf belongs to 5d transition series but it is quite difficult to separate them. Why?
How would you account for the following:
There is a greater range of oxidation states among the actinoids than among the lanthanides.
In lanthanoid the last electron enters (n - 2)f subshell where n is equal to ______.
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of _______.
Which one of the lanthanoids given below is the most stable in divalent form?
State a reason for the following:
La(OH)3 is more basic than Lu(OH)3.
