The pyknometric density of sodium chloride crystal is 2.165 × 103 kg m–3 while its X-ray density is 2.178 × 103 kg m–3. The fraction of unoccupied sites in sodium chloride crystal is:
1. 5.96
2. 5.96 × 10–2
3. 5.96 × 10–1
4. 5.96 × 10–3
Zn converts its melted state to its solid state. It has an HCP structure. The number of the nearest atom is:
1. 6
2. 8
3. 12
4. 4
The number of tetrahedral and octahedral voids in hexagonal primitive unit cell are respectively:
1. 2, 1
2. 12, 6
3. 8, 4
4. 6, 12
The correct option for the number of body centred unit cells in all 14 types of Bravais lattice unit cells is :
1. 2
2. 3
3. 7
4. 5
MgO and NaCl has similar structure. In MgO, magnesium is surrounded by how many oxygen atoms?
1. 2
2. 4
3. 6
4. 1
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
On the basis of unit cell concept a crystal has:
1. 7 systems
2. 14 systems
3. 230 systems
4. 32 systems
The number of atoms per unit cell in a BCC structure is:
1. 9
2. 4
3. 2
4. 1
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
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. |