Calculations Involving Unit Cell Dimensions
CHXII01:THE SOLID STATE

318667 Ice crystallises in a hexagonal lattice having the volume of unit cell as \(132 \times 10^{-24} \mathrm{~cm}^{3}\). If density is \(0.92 \mathrm{~g} \mathrm{~cm}^{-3}\) at a given temperature, then number of \(\mathrm{H}_{2} \mathrm{O}\) molecules per unit cell is

1 4
2 1
3 2
4 3
CHXII01:THE SOLID STATE

318668 Iron exhibits bcc structure at room temperature. Above \(900^{\circ} \mathrm{C}\), it transforms to fcc structure. The ratio of density of iron at room temperature to that at \(900^{\circ} \mathrm{C}\) (assuming molar mass and atomic radii of iron remains constant with temperature) is

1 \(\dfrac{3 \sqrt{3}}{4 \sqrt{2}}\)
2 \(\dfrac{1}{2}\)
3 \(\dfrac{4 \sqrt{3}}{3 \sqrt{2}}\)
4 \(\dfrac{\sqrt{3}}{\sqrt{2}}\)
CHXII01:THE SOLID STATE

318669 A crystalline solid of a pure substance has fcc structure with a cell edge of 400 pm . If the density of the substance in the crystal is \({\rm{8}}\;{\rm{g}}\;{\rm{c}}{{\rm{m}}^{ - {\rm{3}}}}\), then the number of atoms present in 256 g of the crystal is

1 \(2 \times {10^{29}}\)
2 \(0.2 \times {10^{20}}\)
3 \(5 \times {10^{20}}\)
4 \(6 \times {10^{23}}\)
CHXII01:THE SOLID STATE

318670 An element crystallises in a bcc lattice with cell edge of \(500 \mathrm{pm}\). The density of the element is \(7.5 \mathrm{~g} \mathrm{~cm}^{-3}\). How many atoms are present in 300 \(\mathrm{g}\) of metal?

1 \(6.4 \times 10^{23}\) atoms
2 \(12.8 \times 10^{23}\) atoms
3 \(3.2 \times 10^{23}\) atoms
4 \(1.6 \times 10^{23}\) atoms
CHXII01:THE SOLID STATE

318667 Ice crystallises in a hexagonal lattice having the volume of unit cell as \(132 \times 10^{-24} \mathrm{~cm}^{3}\). If density is \(0.92 \mathrm{~g} \mathrm{~cm}^{-3}\) at a given temperature, then number of \(\mathrm{H}_{2} \mathrm{O}\) molecules per unit cell is

1 4
2 1
3 2
4 3
CHXII01:THE SOLID STATE

318668 Iron exhibits bcc structure at room temperature. Above \(900^{\circ} \mathrm{C}\), it transforms to fcc structure. The ratio of density of iron at room temperature to that at \(900^{\circ} \mathrm{C}\) (assuming molar mass and atomic radii of iron remains constant with temperature) is

1 \(\dfrac{3 \sqrt{3}}{4 \sqrt{2}}\)
2 \(\dfrac{1}{2}\)
3 \(\dfrac{4 \sqrt{3}}{3 \sqrt{2}}\)
4 \(\dfrac{\sqrt{3}}{\sqrt{2}}\)
CHXII01:THE SOLID STATE

318669 A crystalline solid of a pure substance has fcc structure with a cell edge of 400 pm . If the density of the substance in the crystal is \({\rm{8}}\;{\rm{g}}\;{\rm{c}}{{\rm{m}}^{ - {\rm{3}}}}\), then the number of atoms present in 256 g of the crystal is

1 \(2 \times {10^{29}}\)
2 \(0.2 \times {10^{20}}\)
3 \(5 \times {10^{20}}\)
4 \(6 \times {10^{23}}\)
CHXII01:THE SOLID STATE

318670 An element crystallises in a bcc lattice with cell edge of \(500 \mathrm{pm}\). The density of the element is \(7.5 \mathrm{~g} \mathrm{~cm}^{-3}\). How many atoms are present in 300 \(\mathrm{g}\) of metal?

1 \(6.4 \times 10^{23}\) atoms
2 \(12.8 \times 10^{23}\) atoms
3 \(3.2 \times 10^{23}\) atoms
4 \(1.6 \times 10^{23}\) atoms
CHXII01:THE SOLID STATE

318667 Ice crystallises in a hexagonal lattice having the volume of unit cell as \(132 \times 10^{-24} \mathrm{~cm}^{3}\). If density is \(0.92 \mathrm{~g} \mathrm{~cm}^{-3}\) at a given temperature, then number of \(\mathrm{H}_{2} \mathrm{O}\) molecules per unit cell is

1 4
2 1
3 2
4 3
CHXII01:THE SOLID STATE

318668 Iron exhibits bcc structure at room temperature. Above \(900^{\circ} \mathrm{C}\), it transforms to fcc structure. The ratio of density of iron at room temperature to that at \(900^{\circ} \mathrm{C}\) (assuming molar mass and atomic radii of iron remains constant with temperature) is

1 \(\dfrac{3 \sqrt{3}}{4 \sqrt{2}}\)
2 \(\dfrac{1}{2}\)
3 \(\dfrac{4 \sqrt{3}}{3 \sqrt{2}}\)
4 \(\dfrac{\sqrt{3}}{\sqrt{2}}\)
CHXII01:THE SOLID STATE

318669 A crystalline solid of a pure substance has fcc structure with a cell edge of 400 pm . If the density of the substance in the crystal is \({\rm{8}}\;{\rm{g}}\;{\rm{c}}{{\rm{m}}^{ - {\rm{3}}}}\), then the number of atoms present in 256 g of the crystal is

1 \(2 \times {10^{29}}\)
2 \(0.2 \times {10^{20}}\)
3 \(5 \times {10^{20}}\)
4 \(6 \times {10^{23}}\)
CHXII01:THE SOLID STATE

318670 An element crystallises in a bcc lattice with cell edge of \(500 \mathrm{pm}\). The density of the element is \(7.5 \mathrm{~g} \mathrm{~cm}^{-3}\). How many atoms are present in 300 \(\mathrm{g}\) of metal?

1 \(6.4 \times 10^{23}\) atoms
2 \(12.8 \times 10^{23}\) atoms
3 \(3.2 \times 10^{23}\) atoms
4 \(1.6 \times 10^{23}\) atoms
CHXII01:THE SOLID STATE

318667 Ice crystallises in a hexagonal lattice having the volume of unit cell as \(132 \times 10^{-24} \mathrm{~cm}^{3}\). If density is \(0.92 \mathrm{~g} \mathrm{~cm}^{-3}\) at a given temperature, then number of \(\mathrm{H}_{2} \mathrm{O}\) molecules per unit cell is

1 4
2 1
3 2
4 3
CHXII01:THE SOLID STATE

318668 Iron exhibits bcc structure at room temperature. Above \(900^{\circ} \mathrm{C}\), it transforms to fcc structure. The ratio of density of iron at room temperature to that at \(900^{\circ} \mathrm{C}\) (assuming molar mass and atomic radii of iron remains constant with temperature) is

1 \(\dfrac{3 \sqrt{3}}{4 \sqrt{2}}\)
2 \(\dfrac{1}{2}\)
3 \(\dfrac{4 \sqrt{3}}{3 \sqrt{2}}\)
4 \(\dfrac{\sqrt{3}}{\sqrt{2}}\)
CHXII01:THE SOLID STATE

318669 A crystalline solid of a pure substance has fcc structure with a cell edge of 400 pm . If the density of the substance in the crystal is \({\rm{8}}\;{\rm{g}}\;{\rm{c}}{{\rm{m}}^{ - {\rm{3}}}}\), then the number of atoms present in 256 g of the crystal is

1 \(2 \times {10^{29}}\)
2 \(0.2 \times {10^{20}}\)
3 \(5 \times {10^{20}}\)
4 \(6 \times {10^{23}}\)
CHXII01:THE SOLID STATE

318670 An element crystallises in a bcc lattice with cell edge of \(500 \mathrm{pm}\). The density of the element is \(7.5 \mathrm{~g} \mathrm{~cm}^{-3}\). How many atoms are present in 300 \(\mathrm{g}\) of metal?

1 \(6.4 \times 10^{23}\) atoms
2 \(12.8 \times 10^{23}\) atoms
3 \(3.2 \times 10^{23}\) atoms
4 \(1.6 \times 10^{23}\) atoms