CBSE
Total volume of atoms present in a face centred cubic unit cell of a metal is (r is atomic radius)
If a be the edge length of the unit cell and r be the radius of an atom then for fee arrangement, the correct relation is
4a = r
4r = a
4r = a
4r =
KF has ccp structure. How many F- ions and octahedral voids are there in this unit cell respectively?
4 and 4
4 and 8
8 and 4
6 and 6
A solid AB has the NaCl structure. If radius of cation A+ is 120 pm, the maximum possible value of the radius of the anion B- is
240 pm
60 pm
49.6 pm
290 pm
Which of the following statement regarding defect is correct.
Due to Schottky defect, the density of crystalline solid decreases.
Due to Frenkel defect, the density of crystalline solid decreases.
Due to Schottky defect, entropy of solid decreases.
Due to Frenkel defect, entropy of solid decreases.
Certain crystals produce electric signals on application of perssure. This phenomenon is called :
pyroelectricity
ferroelectricity
piezoelectricity
ferrielectricity
The number of atoms contained in a fee unit cell of a monoatomic substance is
1
2
4
6
A metallic element has a cubic lattice with edge length of unit cell of 2Å and density is 2.5g cm-1. The number of unit cells in 200g of metal are :
1 1024
1 1020
1 1025
1 1022
In a face-centered cubic lattice, a unit cell is shared equally by how many unit cells?
8
4
2
6
Which of the following arrangements correctly represents hexagonal and cubic close packed structure respectively?
ABAB. .. and ACBACB ......
ABCABC....... and ABAB
Both have ABCABC.....arrangement
Both have ABAB.... arrangement