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प्रश्न
Gadolinium belongs to 4f series. It’s atomic number is 64. Which of the following is the correct electronic configuration of gadolinium?
विकल्प
\[{[Xe] 4f^75d^16s^2}\]
\[{[Xe] 4f^65d^26s^2}\]
\[{[Xe] 4f^86d^2}\]
\[{[Xe] 4f^95d^1}\]
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उत्तर
\[{[Xe] 4f^75d^16s^2}\]
Explanation:
Gadolinium belongs to the 4f series; it has atomic no.= 64. It has extra stability due to a half-filled 4f subshell.
\[\ce{Gd (Z = 64) -> [Xe] 4f^6 5d^2 6s^2}\]
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संबंधित प्रश्न
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Zr and Hf have almost similar atomic radii.
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What are the consequences of lanthanoid contraction?
Explain the cause of Lanthanoids contraction.
What is lanthanoid contraction?
Although +3 oxidation states is the characteristic oxidation state of lanthanoids but cerium shows +4 oxidation state also. Why?
Match the statements given in Column I with the oxidation states given in Column II.
| Column I | Column II | |
| (i) | Oxidation state of Mn in MnO2 is | (a) + 2 |
| (ii) | Most stable oxidation state of Mn is | (b) + 3 |
| (iii) | Most stable oxidation state of | (c) + 4 |
| Mn in oxides is | (d) + 5 | |
| (iv) | Characteristic oxidation state of lanthanoids is | (e) + 7 |
Match the property given in Column I with the element given in Column II.
| Column I (Property) | Column II (Element) | |
| (i) | Lanthanoid which shows +4 oxidation state |
(a) Pm |
| (ii) | Lanthanoid which can show +2 oxidation state |
(b) Ce |
| (iii) | Radioactive lanthanoid | (c) Lu |
| (iv) | Lanthanoid which has 4f7 electronic configuration in +3 oxidation state |
(d) Eu |
| (v) | Lanthanoid which has 4f14 electronic configuration in +3 oxidation state |
(e) Gd |
| (f) Dy |
On the basis of Lanthanoid contraction, explain the following:
Radii of 4d and 5d block elements.
How would you account for the following:
There is a greater range of oxidation states among the actinoids than among the lanthanides.
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of ______.
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La(OH)3 is more basic than Lu(OH)3.
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Name an important alloy which contains some of the lanthanoid metals.
Name an important alloy which contains some of the lanthanoid metals. Mention its uses.
