The lanthanoids
CHXII08:THE D- & F-BLOCK ELEMENTS

321678 Arrange \(\mathrm{\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}}\) and \(\mathrm{\mathrm{Yb}^{3+}}\) in the increasing order of their ionic radii :

1 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{Ce}^{3+} < \mathrm{La}^{3+}}\)
2 \(\mathrm{\mathrm{Ce}^{3+} < \mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+}}\)
3 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+}}\)
4 \(\mathrm{\mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+} < \mathrm{Yb}^{3+}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321679 Identify the wrong statement/s considering Lanthanoid contraction as the basis.
(i) As the size decreases covalent character increases. Therefore, \(\mathrm{\mathrm{La}_{2} \mathrm{O}_{3}}\) is more ionic and \(\mathrm{\mathrm{Lu}_{2} \mathrm{O}_{3}}\) is more covalent.
(ii) As the size decreases from \(\mathrm{\mathrm{La}}\) to \(\mathrm{\mathrm{Lu}}\), stability of oxosalts also decreases.
(iii) Stability of complexes increases as the size of lanthanoids decreases.
(iv) Radii of \({\rm{4d}}\,\,{\rm{and}}\,\,{\rm{5d}}\) block elements will be almost same.
(v) Acidic character of oxides decreases from La to \(\mathrm{\mathrm{Lu}}\).

1 \(\mathrm{\mathrm{i}}\)
2 ii,iii
3 \(\mathrm{v}\)
4 ii,iv
CHXII08:THE D- & F-BLOCK ELEMENTS

321680 The trivalent ion having largest size in lanthanide series is

1 \(\mathrm{Ti}\)
2 \(\mathrm{Zr}\)
3 \(\mathrm{Hf}\)
4 La
CHXII08:THE D- & F-BLOCK ELEMENTS

321681 The correct increasing order of ionic radii of the following \({\rm{C}}{{\rm{e}}^{3 + }},{\rm{L}}{{\rm{a}}^{3 + }},{\rm{P}}{{\rm{m}}^{3 + }}{\rm{ and\, Y}}{{\rm{b}}^{3 + }}{\rm{ is }}\)

1 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ }}\)
2 \({\rm{C}}{{\rm{e}}^{3 + }} < {\rm{Y}}{{\rm{b}}^{3 + }} < {\rm{P}}{{\rm{m}}^{3 + }} < {\rm{L}}{{\rm{a}}^{3 + }}{\rm{ }}\)
3 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ }}\)
4 \({\rm{P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < Y}}{{\rm{b}}^{{\rm{3 + }}}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321682 Select the INCORRECT statement.

1 Shielding effect of f-electrons are minimum out of all the electrons of N -shell.
2 As the f electrons increase, \({{\text{Z}}_{{\text{eff}}}}\) on outer electron decreases in lanthanides.
3 \(\mathrm{Z}_{\text {eff }}\) on outer electron is \(\mathrm{Lu}>\mathrm{La}\).
4 In lanthanide series, electrons are filled in ( \(\mathrm{n}-2) \mathrm{f}\) subshell.
CHXII08:THE D- & F-BLOCK ELEMENTS

321678 Arrange \(\mathrm{\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}}\) and \(\mathrm{\mathrm{Yb}^{3+}}\) in the increasing order of their ionic radii :

1 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{Ce}^{3+} < \mathrm{La}^{3+}}\)
2 \(\mathrm{\mathrm{Ce}^{3+} < \mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+}}\)
3 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+}}\)
4 \(\mathrm{\mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+} < \mathrm{Yb}^{3+}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321679 Identify the wrong statement/s considering Lanthanoid contraction as the basis.
(i) As the size decreases covalent character increases. Therefore, \(\mathrm{\mathrm{La}_{2} \mathrm{O}_{3}}\) is more ionic and \(\mathrm{\mathrm{Lu}_{2} \mathrm{O}_{3}}\) is more covalent.
(ii) As the size decreases from \(\mathrm{\mathrm{La}}\) to \(\mathrm{\mathrm{Lu}}\), stability of oxosalts also decreases.
(iii) Stability of complexes increases as the size of lanthanoids decreases.
(iv) Radii of \({\rm{4d}}\,\,{\rm{and}}\,\,{\rm{5d}}\) block elements will be almost same.
(v) Acidic character of oxides decreases from La to \(\mathrm{\mathrm{Lu}}\).

1 \(\mathrm{\mathrm{i}}\)
2 ii,iii
3 \(\mathrm{v}\)
4 ii,iv
CHXII08:THE D- & F-BLOCK ELEMENTS

321680 The trivalent ion having largest size in lanthanide series is

1 \(\mathrm{Ti}\)
2 \(\mathrm{Zr}\)
3 \(\mathrm{Hf}\)
4 La
CHXII08:THE D- & F-BLOCK ELEMENTS

321681 The correct increasing order of ionic radii of the following \({\rm{C}}{{\rm{e}}^{3 + }},{\rm{L}}{{\rm{a}}^{3 + }},{\rm{P}}{{\rm{m}}^{3 + }}{\rm{ and\, Y}}{{\rm{b}}^{3 + }}{\rm{ is }}\)

1 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ }}\)
2 \({\rm{C}}{{\rm{e}}^{3 + }} < {\rm{Y}}{{\rm{b}}^{3 + }} < {\rm{P}}{{\rm{m}}^{3 + }} < {\rm{L}}{{\rm{a}}^{3 + }}{\rm{ }}\)
3 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ }}\)
4 \({\rm{P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < Y}}{{\rm{b}}^{{\rm{3 + }}}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321682 Select the INCORRECT statement.

1 Shielding effect of f-electrons are minimum out of all the electrons of N -shell.
2 As the f electrons increase, \({{\text{Z}}_{{\text{eff}}}}\) on outer electron decreases in lanthanides.
3 \(\mathrm{Z}_{\text {eff }}\) on outer electron is \(\mathrm{Lu}>\mathrm{La}\).
4 In lanthanide series, electrons are filled in ( \(\mathrm{n}-2) \mathrm{f}\) subshell.
CHXII08:THE D- & F-BLOCK ELEMENTS

321678 Arrange \(\mathrm{\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}}\) and \(\mathrm{\mathrm{Yb}^{3+}}\) in the increasing order of their ionic radii :

1 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{Ce}^{3+} < \mathrm{La}^{3+}}\)
2 \(\mathrm{\mathrm{Ce}^{3+} < \mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+}}\)
3 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+}}\)
4 \(\mathrm{\mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+} < \mathrm{Yb}^{3+}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321679 Identify the wrong statement/s considering Lanthanoid contraction as the basis.
(i) As the size decreases covalent character increases. Therefore, \(\mathrm{\mathrm{La}_{2} \mathrm{O}_{3}}\) is more ionic and \(\mathrm{\mathrm{Lu}_{2} \mathrm{O}_{3}}\) is more covalent.
(ii) As the size decreases from \(\mathrm{\mathrm{La}}\) to \(\mathrm{\mathrm{Lu}}\), stability of oxosalts also decreases.
(iii) Stability of complexes increases as the size of lanthanoids decreases.
(iv) Radii of \({\rm{4d}}\,\,{\rm{and}}\,\,{\rm{5d}}\) block elements will be almost same.
(v) Acidic character of oxides decreases from La to \(\mathrm{\mathrm{Lu}}\).

1 \(\mathrm{\mathrm{i}}\)
2 ii,iii
3 \(\mathrm{v}\)
4 ii,iv
CHXII08:THE D- & F-BLOCK ELEMENTS

321680 The trivalent ion having largest size in lanthanide series is

1 \(\mathrm{Ti}\)
2 \(\mathrm{Zr}\)
3 \(\mathrm{Hf}\)
4 La
CHXII08:THE D- & F-BLOCK ELEMENTS

321681 The correct increasing order of ionic radii of the following \({\rm{C}}{{\rm{e}}^{3 + }},{\rm{L}}{{\rm{a}}^{3 + }},{\rm{P}}{{\rm{m}}^{3 + }}{\rm{ and\, Y}}{{\rm{b}}^{3 + }}{\rm{ is }}\)

1 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ }}\)
2 \({\rm{C}}{{\rm{e}}^{3 + }} < {\rm{Y}}{{\rm{b}}^{3 + }} < {\rm{P}}{{\rm{m}}^{3 + }} < {\rm{L}}{{\rm{a}}^{3 + }}{\rm{ }}\)
3 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ }}\)
4 \({\rm{P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < Y}}{{\rm{b}}^{{\rm{3 + }}}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321682 Select the INCORRECT statement.

1 Shielding effect of f-electrons are minimum out of all the electrons of N -shell.
2 As the f electrons increase, \({{\text{Z}}_{{\text{eff}}}}\) on outer electron decreases in lanthanides.
3 \(\mathrm{Z}_{\text {eff }}\) on outer electron is \(\mathrm{Lu}>\mathrm{La}\).
4 In lanthanide series, electrons are filled in ( \(\mathrm{n}-2) \mathrm{f}\) subshell.
CHXII08:THE D- & F-BLOCK ELEMENTS

321678 Arrange \(\mathrm{\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}}\) and \(\mathrm{\mathrm{Yb}^{3+}}\) in the increasing order of their ionic radii :

1 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{Ce}^{3+} < \mathrm{La}^{3+}}\)
2 \(\mathrm{\mathrm{Ce}^{3+} < \mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+}}\)
3 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+}}\)
4 \(\mathrm{\mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+} < \mathrm{Yb}^{3+}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321679 Identify the wrong statement/s considering Lanthanoid contraction as the basis.
(i) As the size decreases covalent character increases. Therefore, \(\mathrm{\mathrm{La}_{2} \mathrm{O}_{3}}\) is more ionic and \(\mathrm{\mathrm{Lu}_{2} \mathrm{O}_{3}}\) is more covalent.
(ii) As the size decreases from \(\mathrm{\mathrm{La}}\) to \(\mathrm{\mathrm{Lu}}\), stability of oxosalts also decreases.
(iii) Stability of complexes increases as the size of lanthanoids decreases.
(iv) Radii of \({\rm{4d}}\,\,{\rm{and}}\,\,{\rm{5d}}\) block elements will be almost same.
(v) Acidic character of oxides decreases from La to \(\mathrm{\mathrm{Lu}}\).

1 \(\mathrm{\mathrm{i}}\)
2 ii,iii
3 \(\mathrm{v}\)
4 ii,iv
CHXII08:THE D- & F-BLOCK ELEMENTS

321680 The trivalent ion having largest size in lanthanide series is

1 \(\mathrm{Ti}\)
2 \(\mathrm{Zr}\)
3 \(\mathrm{Hf}\)
4 La
CHXII08:THE D- & F-BLOCK ELEMENTS

321681 The correct increasing order of ionic radii of the following \({\rm{C}}{{\rm{e}}^{3 + }},{\rm{L}}{{\rm{a}}^{3 + }},{\rm{P}}{{\rm{m}}^{3 + }}{\rm{ and\, Y}}{{\rm{b}}^{3 + }}{\rm{ is }}\)

1 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ }}\)
2 \({\rm{C}}{{\rm{e}}^{3 + }} < {\rm{Y}}{{\rm{b}}^{3 + }} < {\rm{P}}{{\rm{m}}^{3 + }} < {\rm{L}}{{\rm{a}}^{3 + }}{\rm{ }}\)
3 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ }}\)
4 \({\rm{P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < Y}}{{\rm{b}}^{{\rm{3 + }}}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321682 Select the INCORRECT statement.

1 Shielding effect of f-electrons are minimum out of all the electrons of N -shell.
2 As the f electrons increase, \({{\text{Z}}_{{\text{eff}}}}\) on outer electron decreases in lanthanides.
3 \(\mathrm{Z}_{\text {eff }}\) on outer electron is \(\mathrm{Lu}>\mathrm{La}\).
4 In lanthanide series, electrons are filled in ( \(\mathrm{n}-2) \mathrm{f}\) subshell.
CHXII08:THE D- & F-BLOCK ELEMENTS

321678 Arrange \(\mathrm{\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}}\) and \(\mathrm{\mathrm{Yb}^{3+}}\) in the increasing order of their ionic radii :

1 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{Ce}^{3+} < \mathrm{La}^{3+}}\)
2 \(\mathrm{\mathrm{Ce}^{3+} < \mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+}}\)
3 \(\mathrm{\mathrm{Yb}^{3+} < \mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+}}\)
4 \(\mathrm{\mathrm{Pm}^{3+} < \mathrm{La}^{3+} < \mathrm{Ce}^{3+} < \mathrm{Yb}^{3+}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321679 Identify the wrong statement/s considering Lanthanoid contraction as the basis.
(i) As the size decreases covalent character increases. Therefore, \(\mathrm{\mathrm{La}_{2} \mathrm{O}_{3}}\) is more ionic and \(\mathrm{\mathrm{Lu}_{2} \mathrm{O}_{3}}\) is more covalent.
(ii) As the size decreases from \(\mathrm{\mathrm{La}}\) to \(\mathrm{\mathrm{Lu}}\), stability of oxosalts also decreases.
(iii) Stability of complexes increases as the size of lanthanoids decreases.
(iv) Radii of \({\rm{4d}}\,\,{\rm{and}}\,\,{\rm{5d}}\) block elements will be almost same.
(v) Acidic character of oxides decreases from La to \(\mathrm{\mathrm{Lu}}\).

1 \(\mathrm{\mathrm{i}}\)
2 ii,iii
3 \(\mathrm{v}\)
4 ii,iv
CHXII08:THE D- & F-BLOCK ELEMENTS

321680 The trivalent ion having largest size in lanthanide series is

1 \(\mathrm{Ti}\)
2 \(\mathrm{Zr}\)
3 \(\mathrm{Hf}\)
4 La
CHXII08:THE D- & F-BLOCK ELEMENTS

321681 The correct increasing order of ionic radii of the following \({\rm{C}}{{\rm{e}}^{3 + }},{\rm{L}}{{\rm{a}}^{3 + }},{\rm{P}}{{\rm{m}}^{3 + }}{\rm{ and\, Y}}{{\rm{b}}^{3 + }}{\rm{ is }}\)

1 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ }}\)
2 \({\rm{C}}{{\rm{e}}^{3 + }} < {\rm{Y}}{{\rm{b}}^{3 + }} < {\rm{P}}{{\rm{m}}^{3 + }} < {\rm{L}}{{\rm{a}}^{3 + }}{\rm{ }}\)
3 \({\rm{Y}}{{\rm{b}}^{{\rm{3 + }}}}{\rm{ < P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ }}\)
4 \({\rm{P}}{{\rm{m}}^{{\rm{3 + }}}}{\rm{ < L}}{{\rm{a}}^{{\rm{3 + }}}}{\rm{ < C}}{{\rm{e}}^{{\rm{3 + }}}}{\rm{ < Y}}{{\rm{b}}^{{\rm{3 + }}}}\)
CHXII08:THE D- & F-BLOCK ELEMENTS

321682 Select the INCORRECT statement.

1 Shielding effect of f-electrons are minimum out of all the electrons of N -shell.
2 As the f electrons increase, \({{\text{Z}}_{{\text{eff}}}}\) on outer electron decreases in lanthanides.
3 \(\mathrm{Z}_{\text {eff }}\) on outer electron is \(\mathrm{Lu}>\mathrm{La}\).
4 In lanthanide series, electrons are filled in ( \(\mathrm{n}-2) \mathrm{f}\) subshell.