Einsteinium (99) : \({\mathrm{[R n] 5 \mathrm{f}^{11} 6 \mathrm{~d}^{0} 7 \mathrm{~s}^{2}}}\) So, the correct option is (2).
JEE Main - 2024
CHXII08:THE D- & F-BLOCK ELEMENTS
321668
Which of the following is not an actinide?
1 Curium
2 Californium
3 Uranium
4 Terbium
Explanation:
Terbium is a lanthanide as it belongs to 4f-series having configuration \({\rm{[Xe]4}}{{\rm{f}}^{\rm{9}}}{\rm{,6}}{{\rm{s}}^{\rm{2}}}\). However, the remaining members belongs to 5f-series of actinides.
CHXII08:THE D- & F-BLOCK ELEMENTS
321669
The electronic configuration of actinoids cannot be assigned with degree of certainty because of
1 small energy difference between 5f and 6d levels
2 overlapping of inner orbitals
3 free movement of electrons over all the orbitals
4 none of the above.
Explanation:
For the first four actinide elements, \(\mathrm{Th}, \mathrm{Pa}, \mathrm{U}\) and \(\mathrm{Np}\), the difference in energy between \(5\,{\text{f}}\) and \(6\,{\text{d}}\)-orbitals is small. Thus, in these elements (and their ions) electrons may occupy the \(5\,{\text{f}}\) or the \(6\,{\text{d}}\) levels or sometimes both. Later in the actinide series, the 5 -orbitals become appreciably lower in energy. Thus, from \(\mathrm{Pu}\) onwards the 5 -shell fills in a regular way and the elements become very similar.
CHXII08:THE D- & F-BLOCK ELEMENTS
321670
Which subshell is filled up progressively in actinoids?
1 \(\mathrm{4 \mathrm{f}}\)
2 \(\mathrm{5 \mathrm{f}}\)
3 \(\mathrm{6 d}\)
4 \({\rm{7s}}\)
Explanation:
In case of actinoids, \(\mathrm{5 \mathrm{f}}\) orbital is progressively filled.
CHXII08:THE D- & F-BLOCK ELEMENTS
321671
Assertion : Actinides are highly electropositive metals. Reason : Actinides have same valency.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Actinides exhibit variable valency owing to the extremely small energy differences between their \(5 \mathrm{f}, 6 \mathrm{~d}\), and \(7 \mathrm{~s}\) orbitals. This proximity in energy levels allows for facile changes in oxidation states, contributing to the wide range of valencies observed in these elements. Therefore, option (3) is correct.
Einsteinium (99) : \({\mathrm{[R n] 5 \mathrm{f}^{11} 6 \mathrm{~d}^{0} 7 \mathrm{~s}^{2}}}\) So, the correct option is (2).
JEE Main - 2024
CHXII08:THE D- & F-BLOCK ELEMENTS
321668
Which of the following is not an actinide?
1 Curium
2 Californium
3 Uranium
4 Terbium
Explanation:
Terbium is a lanthanide as it belongs to 4f-series having configuration \({\rm{[Xe]4}}{{\rm{f}}^{\rm{9}}}{\rm{,6}}{{\rm{s}}^{\rm{2}}}\). However, the remaining members belongs to 5f-series of actinides.
CHXII08:THE D- & F-BLOCK ELEMENTS
321669
The electronic configuration of actinoids cannot be assigned with degree of certainty because of
1 small energy difference between 5f and 6d levels
2 overlapping of inner orbitals
3 free movement of electrons over all the orbitals
4 none of the above.
Explanation:
For the first four actinide elements, \(\mathrm{Th}, \mathrm{Pa}, \mathrm{U}\) and \(\mathrm{Np}\), the difference in energy between \(5\,{\text{f}}\) and \(6\,{\text{d}}\)-orbitals is small. Thus, in these elements (and their ions) electrons may occupy the \(5\,{\text{f}}\) or the \(6\,{\text{d}}\) levels or sometimes both. Later in the actinide series, the 5 -orbitals become appreciably lower in energy. Thus, from \(\mathrm{Pu}\) onwards the 5 -shell fills in a regular way and the elements become very similar.
CHXII08:THE D- & F-BLOCK ELEMENTS
321670
Which subshell is filled up progressively in actinoids?
1 \(\mathrm{4 \mathrm{f}}\)
2 \(\mathrm{5 \mathrm{f}}\)
3 \(\mathrm{6 d}\)
4 \({\rm{7s}}\)
Explanation:
In case of actinoids, \(\mathrm{5 \mathrm{f}}\) orbital is progressively filled.
CHXII08:THE D- & F-BLOCK ELEMENTS
321671
Assertion : Actinides are highly electropositive metals. Reason : Actinides have same valency.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Actinides exhibit variable valency owing to the extremely small energy differences between their \(5 \mathrm{f}, 6 \mathrm{~d}\), and \(7 \mathrm{~s}\) orbitals. This proximity in energy levels allows for facile changes in oxidation states, contributing to the wide range of valencies observed in these elements. Therefore, option (3) is correct.
Einsteinium (99) : \({\mathrm{[R n] 5 \mathrm{f}^{11} 6 \mathrm{~d}^{0} 7 \mathrm{~s}^{2}}}\) So, the correct option is (2).
JEE Main - 2024
CHXII08:THE D- & F-BLOCK ELEMENTS
321668
Which of the following is not an actinide?
1 Curium
2 Californium
3 Uranium
4 Terbium
Explanation:
Terbium is a lanthanide as it belongs to 4f-series having configuration \({\rm{[Xe]4}}{{\rm{f}}^{\rm{9}}}{\rm{,6}}{{\rm{s}}^{\rm{2}}}\). However, the remaining members belongs to 5f-series of actinides.
CHXII08:THE D- & F-BLOCK ELEMENTS
321669
The electronic configuration of actinoids cannot be assigned with degree of certainty because of
1 small energy difference between 5f and 6d levels
2 overlapping of inner orbitals
3 free movement of electrons over all the orbitals
4 none of the above.
Explanation:
For the first four actinide elements, \(\mathrm{Th}, \mathrm{Pa}, \mathrm{U}\) and \(\mathrm{Np}\), the difference in energy between \(5\,{\text{f}}\) and \(6\,{\text{d}}\)-orbitals is small. Thus, in these elements (and their ions) electrons may occupy the \(5\,{\text{f}}\) or the \(6\,{\text{d}}\) levels or sometimes both. Later in the actinide series, the 5 -orbitals become appreciably lower in energy. Thus, from \(\mathrm{Pu}\) onwards the 5 -shell fills in a regular way and the elements become very similar.
CHXII08:THE D- & F-BLOCK ELEMENTS
321670
Which subshell is filled up progressively in actinoids?
1 \(\mathrm{4 \mathrm{f}}\)
2 \(\mathrm{5 \mathrm{f}}\)
3 \(\mathrm{6 d}\)
4 \({\rm{7s}}\)
Explanation:
In case of actinoids, \(\mathrm{5 \mathrm{f}}\) orbital is progressively filled.
CHXII08:THE D- & F-BLOCK ELEMENTS
321671
Assertion : Actinides are highly electropositive metals. Reason : Actinides have same valency.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Actinides exhibit variable valency owing to the extremely small energy differences between their \(5 \mathrm{f}, 6 \mathrm{~d}\), and \(7 \mathrm{~s}\) orbitals. This proximity in energy levels allows for facile changes in oxidation states, contributing to the wide range of valencies observed in these elements. Therefore, option (3) is correct.
Einsteinium (99) : \({\mathrm{[R n] 5 \mathrm{f}^{11} 6 \mathrm{~d}^{0} 7 \mathrm{~s}^{2}}}\) So, the correct option is (2).
JEE Main - 2024
CHXII08:THE D- & F-BLOCK ELEMENTS
321668
Which of the following is not an actinide?
1 Curium
2 Californium
3 Uranium
4 Terbium
Explanation:
Terbium is a lanthanide as it belongs to 4f-series having configuration \({\rm{[Xe]4}}{{\rm{f}}^{\rm{9}}}{\rm{,6}}{{\rm{s}}^{\rm{2}}}\). However, the remaining members belongs to 5f-series of actinides.
CHXII08:THE D- & F-BLOCK ELEMENTS
321669
The electronic configuration of actinoids cannot be assigned with degree of certainty because of
1 small energy difference between 5f and 6d levels
2 overlapping of inner orbitals
3 free movement of electrons over all the orbitals
4 none of the above.
Explanation:
For the first four actinide elements, \(\mathrm{Th}, \mathrm{Pa}, \mathrm{U}\) and \(\mathrm{Np}\), the difference in energy between \(5\,{\text{f}}\) and \(6\,{\text{d}}\)-orbitals is small. Thus, in these elements (and their ions) electrons may occupy the \(5\,{\text{f}}\) or the \(6\,{\text{d}}\) levels or sometimes both. Later in the actinide series, the 5 -orbitals become appreciably lower in energy. Thus, from \(\mathrm{Pu}\) onwards the 5 -shell fills in a regular way and the elements become very similar.
CHXII08:THE D- & F-BLOCK ELEMENTS
321670
Which subshell is filled up progressively in actinoids?
1 \(\mathrm{4 \mathrm{f}}\)
2 \(\mathrm{5 \mathrm{f}}\)
3 \(\mathrm{6 d}\)
4 \({\rm{7s}}\)
Explanation:
In case of actinoids, \(\mathrm{5 \mathrm{f}}\) orbital is progressively filled.
CHXII08:THE D- & F-BLOCK ELEMENTS
321671
Assertion : Actinides are highly electropositive metals. Reason : Actinides have same valency.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Actinides exhibit variable valency owing to the extremely small energy differences between their \(5 \mathrm{f}, 6 \mathrm{~d}\), and \(7 \mathrm{~s}\) orbitals. This proximity in energy levels allows for facile changes in oxidation states, contributing to the wide range of valencies observed in these elements. Therefore, option (3) is correct.
Einsteinium (99) : \({\mathrm{[R n] 5 \mathrm{f}^{11} 6 \mathrm{~d}^{0} 7 \mathrm{~s}^{2}}}\) So, the correct option is (2).
JEE Main - 2024
CHXII08:THE D- & F-BLOCK ELEMENTS
321668
Which of the following is not an actinide?
1 Curium
2 Californium
3 Uranium
4 Terbium
Explanation:
Terbium is a lanthanide as it belongs to 4f-series having configuration \({\rm{[Xe]4}}{{\rm{f}}^{\rm{9}}}{\rm{,6}}{{\rm{s}}^{\rm{2}}}\). However, the remaining members belongs to 5f-series of actinides.
CHXII08:THE D- & F-BLOCK ELEMENTS
321669
The electronic configuration of actinoids cannot be assigned with degree of certainty because of
1 small energy difference between 5f and 6d levels
2 overlapping of inner orbitals
3 free movement of electrons over all the orbitals
4 none of the above.
Explanation:
For the first four actinide elements, \(\mathrm{Th}, \mathrm{Pa}, \mathrm{U}\) and \(\mathrm{Np}\), the difference in energy between \(5\,{\text{f}}\) and \(6\,{\text{d}}\)-orbitals is small. Thus, in these elements (and their ions) electrons may occupy the \(5\,{\text{f}}\) or the \(6\,{\text{d}}\) levels or sometimes both. Later in the actinide series, the 5 -orbitals become appreciably lower in energy. Thus, from \(\mathrm{Pu}\) onwards the 5 -shell fills in a regular way and the elements become very similar.
CHXII08:THE D- & F-BLOCK ELEMENTS
321670
Which subshell is filled up progressively in actinoids?
1 \(\mathrm{4 \mathrm{f}}\)
2 \(\mathrm{5 \mathrm{f}}\)
3 \(\mathrm{6 d}\)
4 \({\rm{7s}}\)
Explanation:
In case of actinoids, \(\mathrm{5 \mathrm{f}}\) orbital is progressively filled.
CHXII08:THE D- & F-BLOCK ELEMENTS
321671
Assertion : Actinides are highly electropositive metals. Reason : Actinides have same valency.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
Actinides exhibit variable valency owing to the extremely small energy differences between their \(5 \mathrm{f}, 6 \mathrm{~d}\), and \(7 \mathrm{~s}\) orbitals. This proximity in energy levels allows for facile changes in oxidation states, contributing to the wide range of valencies observed in these elements. Therefore, option (3) is correct.
