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:

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