A compounds that can show both, Frenkel as well as Schottky defects is -
1. AgBr
2. AgI
3. NaCl
4. ZnS
Structure of a mixed oxide is cubic close-packed (CCP). The cubic unit cell of mixed oxide is composed of oxide ions. One-fourth of the tetrahedral voids are occupied by divalent metal A and the octahedral voids are occupied by a monovalent metal B. The formula of the oxide is:
1. A2BO2
2. A2B3O4
3. AB2O2
4. ABO2
Copper has a face-centered cubic (fcc) lattice with interatomic spacing equal to 2.54Å. The value of the lattice constant for this lattice is:
1. 3.59Å
2. 2.54 Å
3. 1.27 Å
4. 5.08 Å
The cations and anions are arranged in an alternate form in:
1. Metallic crystal
2. Ionic crystal
3. Co-valent crystal
4. Semi-conductor crystal
A cube of a crystal has an A-atom placed at every corner and B-atom placed at every centre of face. The formula of the compound is:
1. AB
2. AB3
3. A2B2
4. A2B3
Schottky defect shows:
1. | Same number of cation and anions decrease from lattice. |
2. | Cations and anions are replaced from their sites. |
3. | Maximum number of cations and anions are same. |
4. | None of the above. |
The edge length of a face centered unit cubic cell is 508 pm. If the radius of the cation is 110 pm, the radius of the anion is:
1. 144 pm
2. 398 pm
3. 288 pm
4. 618 pm
The number of atoms per unit cell in a BCC structure is:
1. 9
2. 4
3. 2
4. 1
On the basis of unit cell concept a crystal has:
1. 7 systems
2. 14 systems
3. 230 systems
4. 32 systems
A compound formed by elements X and Y crystallizes in a cubic structure in which the X atoms are at the corners of a cube and the Y atoms are at the face centers. The formula of the compound is:
1. X3Y
2. XY
3. XY2
4. XY3