The D And F Block Elements

Chemistry
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Which of the following pairs has almost same colour?

A
B
C
D
Hard
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A larger number of oxidation states are exhibited by the actinides than those by the lanthanides. The main reason being:

A
more reactive nature of the actinides than the lanthanides
B
orbitals are more diffused than the orbitals
C
lesser energy difference between and orbitals than between and orbitals
D
more energy difference between and orbitals than between and orbitals
Hard
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What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid?

A
is oxidized to +7 state of Cr
B
and are formed
C
and are formed
D
is reduced to +3 state of Cr
Hard
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The actinoids exhibit more oxidation states in general than the lanthanoids. This is because:

A
the 5f orbitals are more buried than the 4f orbitals.
B
there is a similarity between 4f and 5f orbitals in their angular part of the wave function.
C
the actinoids are more reactive than the lanthanoids.
D
the 5f orbitals extend further from the nucleus than the 4f orbitals.
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The larger number of oxidation states are exhibited by the actinides than those by lanthanoids, the main reason being:

A
more energy difference between 5f and 6d than between 4f and 5d orbitals
B
more reactive nature of the actinoids than the lanthanoids
C
4f orbitals more diffused than the 5f orbitals
D
lesser energy difference between 5f and 6d than between 4f and 5d orbitals
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Regarding the magnetic properties of lanthanides and actinides the correct statement is:

A
Lanthanides are weakly paramagnetic while actinides are strongly paramagnetic.
B
Quenching of orbital contribution is greater in lanthanides than in actinides.
C
5f electrons in actinides are too diffuse and are less effectively shielded which results in considerable quenching of orbital contribution, and hence the magnetic moments of actinides are significantly less than theoretically predicted values.
D
Because of diffused f-electrons there is no quenching of orbital contribution towards magnetic moment.
Hard
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The actinoids exhibit more number of oxidation states in general than lanthanoids because: 

A
the 5f orbitals are more buried than the 4f orbitals
B
there is a similarity between 4f and 5f orbitals in their angular part of the wave function
C
the actinoids are more reactive than the lanthanoids
D
the 5f orbitals extend further from the nucleus than the 4f orbitals
Hard
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