Voids

Q.

A crystallizes in HCP close packing and B occupied $\frac{1}{2}$ of octahedral voids.

Calculate the formula of the compound?

What if 2 ions of A are removed from the corner of each unit cell?

What is the new crystal formula?

1. A₂B , A₁₇B₉ respectively

2. A₄B , A₁₇B₉ respectively

3. AB ₂ , A₁₇B respectively

4. A₃B , AB₉ respectively

Q.

In a compound oxide ions are present in CCP. $\frac{1}{6}$ th of the tetrahedral voids are occupied cation A and $\frac{1}{3}$ rd of the octahedral voids are occupied by cation B. What is the formula of the compound and what are the charges on A and B respectively.

1. A ⁵⁺ B⁺ O^3- , ABO₃

2. A ⁵⁺ B⁺ O^3- , A₂BO₃

3. A ⁴⁺ B²⁺ O^3- , ABO₃

4. A ⁶⁺ B⁺ O^3- , AB₂O₃

Q.

The number of octahedral voids per lattice site in a FCC lattice is

(Rounded off to the nearest integer)

Q.

Atoms of element B from HCP lattice and those of element A occupy two thirds of tetrahedral voids. What is the formula of the compound formed by elements A and B.

1. A₄B₃

2. A₄B₆

3. A₅B₃

4. A₈B₃

Q.

A crystallizes in HCP close packing and B occupied $\frac{1}{2}$ of octahedral voids.

Calculate the formula of the compound?

What if 2 ions of A are removed from the corner of each unit cell?

What is the new crystal formula?

1. A₄B , A₁₇B₉ respectively

2. AB ₂ , A₁₇B respectively

3. A₃B , AB₉ respectively

4. A₂B , A₁₇B₉ respectively

Q.

If N is the number of spheres in the unit cell, then total no. of tetrahedral voids is

1. 2N

2. N/2

3. 4N

4. N

Q. A solid is made of two elements X and Z. The atoms Z are in CCP arrangement while the atom X occupy two-third of the tetrahedral sites. What is the formula of the compound?

1. XZ₂
2. X₄Z₃
3. X₂Z₃
4. XZ

Q.

In ABAB close packing in 3-D, what are the types of voids present?

1. Tetrahedral voids

2. Octahedral voids

3. ABAB close packing

4. circular voids

Q.

A crystallises in BCC arrangement and ions B occupy ${\frac{1}{3}}^{rd}$ of tetrahedral voids. What is the formula of the crystal?

1. $A_3{B}_2$

2. $A_5{B}_2$

3. $A_3{B}_4$

4. $A_3{B}_4$

Q.

In ABCABC close packing what are the types of voids present?

1. Tetrahedral voids

2. Octahedral voids

3. Decahedral voids

4. Circular voids