The vacant space in the BCC lattice cell is: 

1. 26%

2. 48%

3. 23%

4. 32%

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

1. 1

2. 3

3. 2

4. 4

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

A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion (Y^–) will be:

1. 165.7 pm 

2. 175.1 pm

3. 322.5 pm 

4. 241.5 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 '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. $1\mathrm{a\; :}$ $\sqrt{3}\mathrm{a}$ $:$ $\sqrt{2}\mathrm{a}$

If NaCl is doped with 10^-4mol% of SrCl₂, the concentration of cation vacancies will be (N_A= 6.02×10²³mol^-1):

1. $6.02\times {10}^{15}$ $mo{l}^{-1}$

2. $6.02\times {10}^{16}$ $mo{l}^{-1}$

3. $6.02\times {10}^{17}$ $mo{l}^{-1}$

4. $6.02\times {10}^{14}$ $mo{l}^{-1}$