The correct statement regarding defects in a crystalline solid is:

1.	Schottky defects have no effect on the density of crystalline solids.
2.	Frenkel defects decrease the density of crystalline solids.
3.	Frenkel defect is a dislocation defect.
4.	Frenkel defect is found in halides of alkaline metals.

The vacant space in the BCC lattice cell is: 

1. 26%

2. 48%

3. 23%

4. 32%

A given metal crystallizes out with a cubic structure having an edge length of 361 pm. If there are four metal atoms in one unit cell, the radius of one atom is:

1. 40 pm
2. 127 pm
3. 80 pm
4. 108 pm

If a is the length of the side of a cube, the distance between the body-centered atom and one corner atom in the cube will be:

1. $\frac{2}{\sqrt{3}}a$

2. $\frac{4}{\sqrt{3}}a$

3. $\frac{\sqrt{3}}{4}a$

4. $\frac{\sqrt{3}}{2}a$

The number of carbon atoms per unit cell of a diamond is:

1. 8

2. 6

3. 1

4. 4

A metal crystallizes with a fcc lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is: 

1. 288 pm

2. 408 pm

3. 144 pm

4. 204 pm

The number of octahedral void(s) per atom present in a cubic close-packed structure is: 

1. 1

2. 3

3. 2

4. 4

AB crystallizes in a body-centered cubic lattice with edge length 'a' equal to 387 pm. The distance between two oppositely charged ions in the lattice is:

1. 335 pm

2. 250 pm

3. 200 pm

4. 300 pm