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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?
पर्याय
\[{[Xe] 4f^75d^16s^2}\]
\[{[Xe] 4f^65d^26s^2}\]
\[{[Xe] 4f^86d^2}\]
\[{[Xe] 4f^95d^1}\]
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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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What is lanthanoid contraction?
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) \[\ce{Ho}\]
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| 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 |
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| 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 |
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