- 1(current)
Q. No.Which of the following lanthanide ions has four unpaired electrons?
(Given : Atomic numbers of Ce = 58, Nd = 60, Tb = 65 and Ho = 67)
(Given : Atomic numbers of Ce = 58, Nd = 60, Tb = 65 and Ho = 67)
| 1. | Ho3+ | 2. | Nd3+ |
| 3. | Ce3+ | 4. | Tb3+ |
Subtopic: Â f-Block Elements- Properties & Uses |Â Lanthanoid & Actinoids Contraction |
Level 3: 35%-60%
NEET - 2026
Please attempt this question first.
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Please attempt this question first.
The decrease in size from left to right in the actinoid series is greater and more gradual than that in the lanthanoid series due to:
| 1. | 4f orbitals are penultimate |
| 2. | 4f orbitals have a greater shielding effect |
| 3. | 5f orbitals have a poor shielding effect |
| 4. | 5f orbitals have a greater shielding effect |
Subtopic: Â Lanthanoid & Actinoids Contraction |
 80%
Level 1: 80%+
NEET - 2022
Hints
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of:
| 1. | Lanthanoid contraction |
| 2. | Having similar chemical properties |
| 3. | Belonging to the same group |
| 4. | Diagonal relationship |
Subtopic: Â Lanthanoid & Actinoids Contraction |
 89%
Level 1: 80%+
NEET - 2021
Hints
The incorrect statement among the following is:
| 1. | Lanthanoids are good conductors of heat and electricity. |
| 2. | Actinoids are highly reactive metals, especially when finely divided. |
| 3. | Actinoid contraction is greater for element to element than Lanthanoid contraction. |
| 4. | Most of the trivalent Lanthanoid ions are colourless in the solid-state. |
Subtopic: Â f-Block Elements- Properties & Uses |Â Lanthanoid & Actinoids Contraction |
 62%
Level 2: 60%+
NEET - 2021
Hints
Identify the incorrect statement from the following:
| 1. | Zirconium and Hafnium have identical radii of 160 pm and 159 pm, respectively as a consequence of lanthanoid contraction. |
| 2. | Lanthanoids reveal only +3 oxidation state. |
| 3. | The lanthanoid ions other than the f0 type and the f14 type are all paramagnetic. |
| 4. | The overall decrease in atomic and ionic radii from lanthanum to lutetium is called lanthanoid contraction. |
Subtopic: Â Lanthanoid & Actinoids Contraction |
 70%
Level 2: 60%+
NEET - 2020
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- 1(current)
Q. No.
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