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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)
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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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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+
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Although Zr belongs to 4d and Hf belongs to 5d transition series but it is quite difficult to separate them. Why?
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Although +3 oxidation states is the characteristic oxidation state of lanthanoids but cerium shows +4 oxidation state also. Why?
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Match the compounds/elements given in Column I with uses given in Column II.
| Column I (Compound/element) | Column II (Use) | |
| (i) | Lanthanoid oxide | (a) Production of iron alloy |
| (ii) | Lanthanoid | (b) Television screen |
| (iii) | Misch metal | (c) Petroleum cracking |
| (iv) | Magnesium based alloy is constituent of | (d) Lanthanoid metal + iron |
| (v) | Mixed oxides of lanthanoids are employed | (e) Bullets |
| (f) In X-ray screen |
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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 |
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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 |
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On the basis of Lanthanoid contraction, explain the following:
Nature of bonding in \[\ce{La2O3}\] and \[\ce{Lu2O3}\] .
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On the basis of Lanthanoid contraction, explain the following:
Trends in the stability of oxo salts of lanthanoids from \[\ce{La}\] to \[\ce{Lu}\].
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On the basis of Lanthanoid contraction, explain the following:
Stability of the complexes of lanthanoids.
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On the basis of Lanthanoid contraction, explain the following:
Radii of 4d and 5d block elements.
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On the basis of Lanthanoid contraction, explain the following:
Trends in acidic character of lanthanoid oxides.
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Which of the following reactions will yield phenol?
| (i) |  |
| (ii) |  |
| (iii) |  |
| (iv) |  |
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Name the starting material used in the industrial preparation of phenol.
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Name the electrophile produced in the reaction of benzene with benzoyl chloride in the presence of anhydrous \[\ce{AlCl3}\]. Name the reaction also.
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Ethylbenzene is generally prepared by acetylation of benzene followed by reduction and not by direct alkylation. Think of a possible reason.
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Can Gatterman-Koch reaction be considered similar to Friedel Craft’s acylation? Discuss.
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Match the common names given in Column I with the IUPAC names given in Column II.
| Column I (Common names) |
Column II (IUPAC names) |
||
| (i) | Cinnamaldehyde | (a) | Pentanal |
| (ii) | Acetophenone | (b) | Prop-2-enal |
| (iii) | Valeraldehyde | (c) | 4-Methylpent-3-en-2-one |
| (iv) | Acrolein | (d) | 3-Phenylprop-2-enal |
| (v) | Mesityl oxide | (e) | 1-Phenylethanone |
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Match the acids given in Column I with their correct IUPAC names given in Column II.
| Column I (Acids) |
Column II (IUPAC names) |
||
| (i) | Phthalic acid | (a) | Hexane-1,6-dioic acid |
| (ii) | Oxalic acid | (b) | Benzene-1,2-dicarboxylic acid |
| (iii) | Succinic acid | (c) | Pentane-1,5-dioic acid |
| (iv) | Adipic acid | (d) | Butane-1,4-dioic acid |
| (v) | Glutaric acid | (e) | Ethane-1,2-dioic acid |
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