1. | \(a = 2r\) | 2. | \(a = r /2\sqrt2\) |
3. | \(a = 4r /\sqrt3\) | 4. | \(a = 2\sqrt2r\) |
An element has a body-centered cubic (BCC) structure with a cell edge of 288 pm. The atomic radius is:
1. pm
2. pm
3. pm
4. pm
The formula of nickel oxide with metal deficiency defect in its crystal is . The crystal contains ions. The fraction of nickel existing as ions in the crystal is-
1. 0.96
2. 0.04
3. 0.50
4. 0.31
Iron exhibits bcc structure at room temperature. Above 900 °C, it transforms to fcc structure. The ratio of density of iron at room temperature to that at 900 °C is:
(Molar mass and atomic radii of iron remain constant with temperature)
1.
2.
3.
4.
A given metal crystallizes out with a cubic structure having an edge length of 361 pm. If there are four metal atoms in one unit cell, the radius of one atom is:
1. 40 pm
2. 127 pm
3. 80 pm
4. 108 pm
A metal crystallizes with a fcc lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is:
1. 288 pm
2. 408 pm
3. 144 pm
4. 204 pm