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

MgO and NaCl has similar structure. In MgO, magnesium is surrounded by how many oxygen atoms?
1. 2
2. 4
3. 6
4. 1

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

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

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