Crystal Lattice and Unit Cell

Q. A compound has cubical unit cell in which X atoms are present at 4 corners , Y atoms are present at the remaining corners and only at those face center(s) which is/are not opposite to each other.
The formula for the compound will be:

1. $X{Y}_4$
2. $X{Y}_2$
3. $X_{4}Y$
4. $X_{2}Y$

Q.

Which of the following statement is true about the Lattice?

1. It is a regular repeated three-dimensional arrangement of atoms

2. It is a series of points that are arranged in a distinct pattern.

3. It is an ordered set of points that define the structure of a crystal-forming particle.

4. All of These

Q. Crystals can be classified into....... basic crystal systems.

1. 7
2. 14
3. 4
4. 3

Q. The most unsymmetrical crystal system is:

1. Hexagonal
2. Orthorhombic
3. Cubic
4. Triclinic

Q. The radius of a divalent cation $A^{2+}$ is $94pm$ and that of a divalent anion $B^{2-}$ is $146pm$. The compound $AB$ has:

1. Zinc blende structure
2. Antifluorite structure
3. Caesium chloride like structure
4. Rock salt structure

Q. A compound having cubic structure is formed by the elements X, Y and Z.
Atoms of element X are present at corners and face centres of the cube . Atoms of element Y are present at edges and atoms of element Z are present at body centre.

What will be the simplest formula of the compound if all the atoms are removed from one of the plane which is parallel to either one of the faces of the cube and also passing through middle of the cube?

1. $X_{2}Y{Z}_3$
2. $X_{2}YZ$
3. $X_2{Y}_3$
4. $XY$

Q. The packing efficiency for the 2-dimensional square unit cell shown below is

1. 78.54%
2. 68.02%
3. 74.05%
4. 39.27%

Q. Iron exhibits bcc structure at room temperature. Above ${900}^{\circ }C$, it transforms to fcc structure. The ratio of density of iron at room temperature to that at ${900}^{\circ }C$ (assuming molar mass and atomic radii of iron remains constant with temperature) is:
(NEET 2018)

1. $\frac{\sqrt{3}}{\sqrt{2}}$
2. $\frac{4\sqrt{3}}{3\sqrt{2}}$
3. $\frac{3\sqrt{3}}{4\sqrt{2}}$
4. $\frac{1}{2}$

Q.

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

1. Tetrahedral voids

2. Octahedral voids

3. Decahedral voids

4. Circular voids

Q.

Select the appropriate option.

1. Image 1 is crystal lattice, Image 2 is crystal lattice

2. Image 1 is space lattice, Image 2 is crystal lattice

3. Image 1 is crystal lattice, Image 2 is space lattice

4. Image 1 is space lattice, Image 2 is crystal lattice

Q. A diatomic molecule $X_2$ has a body-centred cubic (bcc) structure with a cell edge of $300pm$. The density of the molecule is $6.17g/c{m}^3$. The number of molecules present in $200g$ of $X_2$ is: $\text{Avogadro constant}\left(N_A\right)=6\times {10}^{23}mo{l}^{-1})$
(JEE Main 2020)

Q.

Match the following:

$\begin{array}{cc}ColumnI& ColumnII\\ 1.Hexagonal& \left(i\right)a=b=c\\ 2.Cubic& \left(ii\right)a\ne b\ne c\\ 3.Triclinic& \left(iii\right)a=b\ne c\\ 4.Monoclinic& \left(iv\right)\alpha =\beta =\gamma =90{}^{\circ }\\ 5.Tetragonal& \left(v\right)\alpha =\gamma =90{}^{\circ },\beta \ne 90{}^{\circ }\\ 6.Rhombohedral& \left(vi\right)\alpha \ne \beta \ne \gamma \ne 90{}^{\circ }\\ 7.Orthorhombic& \left(vii\right).\alpha =\beta =\gamma \ne 90{}^{\circ }\\ & \left(viii\right)\alpha =\beta =90{}^{\circ },\gamma =120{}^{\circ }\end{array}$

1. (1)–(iii), (viii); (2)–(i), (iv); (3)–(ii), (vi); (4)-(ii), (v); (5)–(iii), (iv); (6)–(i) (vii); (7)–(ii), (iv)

2. (1)–(ii), (vii); (2)–(i), (vii); (3)–(iii), (iv); (4)-(i), (v); (5)–(ii), (vi); (6)–(i) (vi); (7)–(i), (iv)

3. (1)–(ii), (vii); (2)–(i), (iv); (3)–(ii), (vi); (4)-(ii), (v); (5)–(ii), (iv); (6)–(i) (viii); (7)–(iii), (iv)

4. (1)–(ii), (vii); (2)–(i), (iv); (3)–(ii), (vi); (4)-(ii), (iv); (5)–(i), (viii); (6)–(iii) (iv); (7)–(iii), (vii)