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

Copper crystallizes in a face-centered cubic lattice with a unit cell length of 361 pm. The radius of the copper atom is:

1. 128 pm

2. 157 pm

3. 181 pm

4. 108 pm

If the lattice parameter for a crystalline structure is 3.6 Å, then the atomic radius in fcc crystal is: 

1. 1.81 Å

2. 2.10 Å

3. 2.92 Å

4. 1.27 Å

Lithium metal crystallizes in a body-centered cubic crystal. If the length of the side of the unit cell of lithium is 351 pm, the atomic radius of the lithium will be:

1. 240.8 pm

2. 151.8 pm

3. 75.5 pm

4. 300.5 pm

If 'a’ stands for the edge length of the cubic systems: simple cubic, body-centered cubic, and face-centered cubic, then the ratio of radii of the spheres in these systems will be respectively: 

1. $\frac{1}{2}\mathrm{a\; :}$ $\frac{\sqrt{3}}{4}\mathrm{a}$ $:$ $\frac{1}{{\displaystyle 2}\sqrt{2}}\mathrm{a}$

2. $\frac{1}{2}\mathrm{a\; :}$ $\sqrt{3}\mathrm{a}$ $:$ $\frac{1}{\sqrt{2}}\mathrm{a}$

3. $\frac{1}{2}\mathrm{a\; :}$ $\frac{\sqrt{3}}{2}\mathrm{a}$ $:$ $\frac{\sqrt{2}}{{\displaystyle 2}}\mathrm{a}$

4. $1\mathrm{a\; :}$ $\sqrt{3}\mathrm{a}$ $:$ $\sqrt{2}\mathrm{a}$

Silicon gives p-type of semiconductor on doping with:

1. Germanium.

2. Arsenic.

3. Selenium.

4. Boron.