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
An ionic compound has a unit cell consisting of A ions at the corners of a cube and B ions on the centers of the faces of the cube. The empirical formula for this compound would be :
1. AB
2. A2B
3. AB3
4. A3B
The edge length of fcc unit cell of NaCl is 508 pm.
If the radius of cation is 110 pm then radius of the anion is :
1. 244 pm
2. 144 pm
3. 288 pm
4. 398 pm
A compound that shows Schottky as well as Frenkel defect among the following is -
1. ZnS
2. AgBr
3. NaCl
4. AgCl
In the spinel structrue, oxides ions are cubical-closest packed whereas 1/8th of tetrahedral voids are occupied by cation and 1/2 of octahedral voids are occupied by cations. The general formula of the compound having spinel structure is :
1.
2.
3.
4.
An element crystallizes in a structure having FCC unit cell of an edge length 200 pm. If
200 g this element contains 24 x 1023 atoms, the density of the element is
1. 50.3 g/cc
2. 63.4 g/cc
3. 41.6 g/cc
4. 34.8 g/cc
Ionic radii of Mg2+ and O2- ions are 66 pm and 140 pm respectively. The type of interstitial void and coordination number of Mg2+ ion respectively are
1. Tetrahedral, 12
2. Octahedral, 6
3. Tetrahedral, 6
4. Octahedral, 8
An element occurring in the bcc structure has unit cells. The total number of atoms of the element in these cells will be:
1.
2.
3.
4.
A compound is formed by cation C and anion A. The anions form hexagonal close packed (hcp) lattice and the cations occupy 75 % of octahedral voids. The formula of the compound is:
1.
2.
3.
4.
If an element (at. Wt. = 50) crystallises in fcc lattice, with a = 0.50 nm, then the density of unit cell if it contains 0.25 % Schottky defect is -
(Use )
1. 2.0 g/cc
2. 2.66 g/cc
3. 3.06 g/cc
4. None of the above.