d- and f- Block Elements  MCQs

MCQs of d- and f- Block Elements

Showing 111 to 120 out of 158 Questions
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111.
Which of the following substance is used to produce very low temperature by magnetic effect ?
(a) CeO2
(b) Lanthanide oxide
(c) Gadolinium sulphate
(d) Thulium sulphate
Answer:

Option (c)

112.
On what does the stability of oxidation state depend in lanthanide elements ?
(a) Heat of hydration and heat of ionization together
(b) Electronic structure
(c) Enthalpy
(d) Internal energy
Answer:

Option (a)

113.
Which compound of a lanthanoid is used in pigments ?
(a) Tb(OH)3
(b) Lu(OH)3
(c) Ce(OH)3
(d) CeO2
Answer:

Option (d)

114.
For which of the following statements is lanthanide contraction responsible ? OR Lanthanide contraction is responsible for _____ .
(a) identical oxidation states of Zn and Zr
(b) approximately equal covalent and ionic radii of Zr and Hf
(c) identical oxidation states of Zr and Nb
(d) approximately equal covalent and ionic radii of Zr and Yb
Answer:

Option (b)

115.
The common stable oxidation state of elements of lanthanide series is +3 (Ln (III)). Which of the following statements is wrong for lanthanoids ?
(a) Ln (III) hydroxides show generally basic behaviour.
(b) Due to bigger volume of Ln (III) ion, it combines forming ionic bonds in its compounds.
(c) Ln (III) compounds are generally colourless.
(d) Ionic volume of Ln(III) decreases as atomic number increases.
Answer:

Option (b)

116.
Give reason for stability of Gd3+ ion.
(a) 4 f- orbitals are fully filled.
(b) 4 f- orbitals are half filled.
(c) It has electronic configuration of an inert gas.
(d) 4 f- orbitals are complexly vacant.
Answer:

Option (b)

117.
Which of the following is not an actinoid ?
(a) Uranium
(b) Curium
(c) Californium
(d) Erbium
Answer:

Option (d)

118.
(i) La(OH)3 is least basic in lanthanoids.

(ii)Zr4+ and Hf4+ have nearly similar ionic radii.

(iii) Ce4+ can act as an oxidizing agent.

Which of the above statements are correct ?

(a) (i) and (iii)
(b) (ii) and (iii)
(c) Only (ii)
(d) (i) and (ii)
Answer:

Option (b)

119.
Which of the following lanthanoids ions is diamagnetic ?

(At. nos. Ce = 58, Sm = 62, Yb = 70)

(a) Ce2+
(b) Sm2+
(c) Eu2+
(d) Yb2+
Answer:

Option (d)

120.
Which of the following elements never shows +6 oxidation state in any of its compounds ?
(a) Ti
(b) Cr
(c) Mn
(d) w
Answer:

Option (a)

Showing 111 to 120 out of 158 Questions
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