F-center is a type of crystallographic defect in which an anionic vacancy in a crystal is filled by one or more unpaired electrons. Therefore, F-centers are lattice sites containing electrons.
CHXII01:THE SOLID STATE
318829
The flame colours of metal ions are due to
1 Frenkel defect
2 Metal deficiency defect
3 Schottky defect
4 Metal excess defect
Explanation:
In metal excess defect when holes created by missing of anions are occupied by electrons, their sites are called F-centres and are responsible for colour in the crystal.
CHXII01:THE SOLID STATE
318830
The non-stoichiometric compound \(\mathrm{Fe}_{0.94} \mathrm{O}\) is formed when \(x \%\) of \(\mathrm{Fe}^{2+}\) ions are replaced by as many \(\dfrac{2}{3} F e^{3+}\) ions, \(\mathrm{x}\) is
1 18
2 12
3 15
4 6
Explanation:
The number of \(\mathrm{Fe}^{3+}\) ions replacing \(\mathrm{x} \mathrm{Fe}^{3+}\) ions \(=\dfrac{2 x}{3}\) Vacancies of cations \(=x-\dfrac{2 x}{3}=\dfrac{x}{3}\) But, \(\quad \dfrac{x}{3}=1-0.94=0.06, \mathrm{x}=0.06 \times 3\) \[ =0.18=18 \% \]
CHXII01:THE SOLID STATE
318831
Match the columns Column I Column II A Impurity defect P NaCl with anionic sites (F - centres) B Metal excess defect Q FeO with \({\rm{F}}{{\rm{e}}^{{\rm{3 + }}}}\) C Metal deficiency defect R NaCl with \({\rm{S}}{{\rm{r}}^{{\rm{2 + }}}}\) and some cationic sites vacant
1 A - R, B - P, C - Q
2 A - P, B - Q, C - R
3 A - R, B - Q, C - P
4 A - Q, B - P, C - R
Explanation:
Conceptual Questions
CHXII01:THE SOLID STATE
318832
Which of the following statements is not correct?
1 Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound.
2 The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals.
3 The compound ferrous oxide can be prepared in its stoichiometric composition.
4 Silver cyanide shows both types of Schottky and Frenkel defects.
Explanation:
\(\mathrm{FeO}\) is a non-stoichiometry defect showing substance.
F-center is a type of crystallographic defect in which an anionic vacancy in a crystal is filled by one or more unpaired electrons. Therefore, F-centers are lattice sites containing electrons.
CHXII01:THE SOLID STATE
318829
The flame colours of metal ions are due to
1 Frenkel defect
2 Metal deficiency defect
3 Schottky defect
4 Metal excess defect
Explanation:
In metal excess defect when holes created by missing of anions are occupied by electrons, their sites are called F-centres and are responsible for colour in the crystal.
CHXII01:THE SOLID STATE
318830
The non-stoichiometric compound \(\mathrm{Fe}_{0.94} \mathrm{O}\) is formed when \(x \%\) of \(\mathrm{Fe}^{2+}\) ions are replaced by as many \(\dfrac{2}{3} F e^{3+}\) ions, \(\mathrm{x}\) is
1 18
2 12
3 15
4 6
Explanation:
The number of \(\mathrm{Fe}^{3+}\) ions replacing \(\mathrm{x} \mathrm{Fe}^{3+}\) ions \(=\dfrac{2 x}{3}\) Vacancies of cations \(=x-\dfrac{2 x}{3}=\dfrac{x}{3}\) But, \(\quad \dfrac{x}{3}=1-0.94=0.06, \mathrm{x}=0.06 \times 3\) \[ =0.18=18 \% \]
CHXII01:THE SOLID STATE
318831
Match the columns Column I Column II A Impurity defect P NaCl with anionic sites (F - centres) B Metal excess defect Q FeO with \({\rm{F}}{{\rm{e}}^{{\rm{3 + }}}}\) C Metal deficiency defect R NaCl with \({\rm{S}}{{\rm{r}}^{{\rm{2 + }}}}\) and some cationic sites vacant
1 A - R, B - P, C - Q
2 A - P, B - Q, C - R
3 A - R, B - Q, C - P
4 A - Q, B - P, C - R
Explanation:
Conceptual Questions
CHXII01:THE SOLID STATE
318832
Which of the following statements is not correct?
1 Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound.
2 The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals.
3 The compound ferrous oxide can be prepared in its stoichiometric composition.
4 Silver cyanide shows both types of Schottky and Frenkel defects.
Explanation:
\(\mathrm{FeO}\) is a non-stoichiometry defect showing substance.
F-center is a type of crystallographic defect in which an anionic vacancy in a crystal is filled by one or more unpaired electrons. Therefore, F-centers are lattice sites containing electrons.
CHXII01:THE SOLID STATE
318829
The flame colours of metal ions are due to
1 Frenkel defect
2 Metal deficiency defect
3 Schottky defect
4 Metal excess defect
Explanation:
In metal excess defect when holes created by missing of anions are occupied by electrons, their sites are called F-centres and are responsible for colour in the crystal.
CHXII01:THE SOLID STATE
318830
The non-stoichiometric compound \(\mathrm{Fe}_{0.94} \mathrm{O}\) is formed when \(x \%\) of \(\mathrm{Fe}^{2+}\) ions are replaced by as many \(\dfrac{2}{3} F e^{3+}\) ions, \(\mathrm{x}\) is
1 18
2 12
3 15
4 6
Explanation:
The number of \(\mathrm{Fe}^{3+}\) ions replacing \(\mathrm{x} \mathrm{Fe}^{3+}\) ions \(=\dfrac{2 x}{3}\) Vacancies of cations \(=x-\dfrac{2 x}{3}=\dfrac{x}{3}\) But, \(\quad \dfrac{x}{3}=1-0.94=0.06, \mathrm{x}=0.06 \times 3\) \[ =0.18=18 \% \]
CHXII01:THE SOLID STATE
318831
Match the columns Column I Column II A Impurity defect P NaCl with anionic sites (F - centres) B Metal excess defect Q FeO with \({\rm{F}}{{\rm{e}}^{{\rm{3 + }}}}\) C Metal deficiency defect R NaCl with \({\rm{S}}{{\rm{r}}^{{\rm{2 + }}}}\) and some cationic sites vacant
1 A - R, B - P, C - Q
2 A - P, B - Q, C - R
3 A - R, B - Q, C - P
4 A - Q, B - P, C - R
Explanation:
Conceptual Questions
CHXII01:THE SOLID STATE
318832
Which of the following statements is not correct?
1 Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound.
2 The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals.
3 The compound ferrous oxide can be prepared in its stoichiometric composition.
4 Silver cyanide shows both types of Schottky and Frenkel defects.
Explanation:
\(\mathrm{FeO}\) is a non-stoichiometry defect showing substance.
F-center is a type of crystallographic defect in which an anionic vacancy in a crystal is filled by one or more unpaired electrons. Therefore, F-centers are lattice sites containing electrons.
CHXII01:THE SOLID STATE
318829
The flame colours of metal ions are due to
1 Frenkel defect
2 Metal deficiency defect
3 Schottky defect
4 Metal excess defect
Explanation:
In metal excess defect when holes created by missing of anions are occupied by electrons, their sites are called F-centres and are responsible for colour in the crystal.
CHXII01:THE SOLID STATE
318830
The non-stoichiometric compound \(\mathrm{Fe}_{0.94} \mathrm{O}\) is formed when \(x \%\) of \(\mathrm{Fe}^{2+}\) ions are replaced by as many \(\dfrac{2}{3} F e^{3+}\) ions, \(\mathrm{x}\) is
1 18
2 12
3 15
4 6
Explanation:
The number of \(\mathrm{Fe}^{3+}\) ions replacing \(\mathrm{x} \mathrm{Fe}^{3+}\) ions \(=\dfrac{2 x}{3}\) Vacancies of cations \(=x-\dfrac{2 x}{3}=\dfrac{x}{3}\) But, \(\quad \dfrac{x}{3}=1-0.94=0.06, \mathrm{x}=0.06 \times 3\) \[ =0.18=18 \% \]
CHXII01:THE SOLID STATE
318831
Match the columns Column I Column II A Impurity defect P NaCl with anionic sites (F - centres) B Metal excess defect Q FeO with \({\rm{F}}{{\rm{e}}^{{\rm{3 + }}}}\) C Metal deficiency defect R NaCl with \({\rm{S}}{{\rm{r}}^{{\rm{2 + }}}}\) and some cationic sites vacant
1 A - R, B - P, C - Q
2 A - P, B - Q, C - R
3 A - R, B - Q, C - P
4 A - Q, B - P, C - R
Explanation:
Conceptual Questions
CHXII01:THE SOLID STATE
318832
Which of the following statements is not correct?
1 Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound.
2 The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals.
3 The compound ferrous oxide can be prepared in its stoichiometric composition.
4 Silver cyanide shows both types of Schottky and Frenkel defects.
Explanation:
\(\mathrm{FeO}\) is a non-stoichiometry defect showing substance.
F-center is a type of crystallographic defect in which an anionic vacancy in a crystal is filled by one or more unpaired electrons. Therefore, F-centers are lattice sites containing electrons.
CHXII01:THE SOLID STATE
318829
The flame colours of metal ions are due to
1 Frenkel defect
2 Metal deficiency defect
3 Schottky defect
4 Metal excess defect
Explanation:
In metal excess defect when holes created by missing of anions are occupied by electrons, their sites are called F-centres and are responsible for colour in the crystal.
CHXII01:THE SOLID STATE
318830
The non-stoichiometric compound \(\mathrm{Fe}_{0.94} \mathrm{O}\) is formed when \(x \%\) of \(\mathrm{Fe}^{2+}\) ions are replaced by as many \(\dfrac{2}{3} F e^{3+}\) ions, \(\mathrm{x}\) is
1 18
2 12
3 15
4 6
Explanation:
The number of \(\mathrm{Fe}^{3+}\) ions replacing \(\mathrm{x} \mathrm{Fe}^{3+}\) ions \(=\dfrac{2 x}{3}\) Vacancies of cations \(=x-\dfrac{2 x}{3}=\dfrac{x}{3}\) But, \(\quad \dfrac{x}{3}=1-0.94=0.06, \mathrm{x}=0.06 \times 3\) \[ =0.18=18 \% \]
CHXII01:THE SOLID STATE
318831
Match the columns Column I Column II A Impurity defect P NaCl with anionic sites (F - centres) B Metal excess defect Q FeO with \({\rm{F}}{{\rm{e}}^{{\rm{3 + }}}}\) C Metal deficiency defect R NaCl with \({\rm{S}}{{\rm{r}}^{{\rm{2 + }}}}\) and some cationic sites vacant
1 A - R, B - P, C - Q
2 A - P, B - Q, C - R
3 A - R, B - Q, C - P
4 A - Q, B - P, C - R
Explanation:
Conceptual Questions
CHXII01:THE SOLID STATE
318832
Which of the following statements is not correct?
1 Heating of zinc oxide leads to the formation of a yellow coloured non-stoichiometric compound.
2 The creation of cationic holes in ionic crystals imparts electrical conductivity to such crystals.
3 The compound ferrous oxide can be prepared in its stoichiometric composition.
4 Silver cyanide shows both types of Schottky and Frenkel defects.
Explanation:
\(\mathrm{FeO}\) is a non-stoichiometry defect showing substance.
