CBSE
Which of the following statements is not correct?
The fraction of the total volume occupied by the atoms in a primitive cell is 0.48
molecules solids are generally volatile
the number of carbon atoms in a unit cell
the number of carbon atoms in a unit cell
With which one of the following elements silicon should be doped so as to give p - type of semiconductor?
Germanium
Arsenic
Selenium
Selenium
The vacant space in bcc lattice cell is
26%
48%
23%
23%
A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion (Y-) will be
275.1 pm
322.5 pm
241.5 pm
241.5 pm
Lithium metal crystallises in a body centred cubic crystal. If the length of the side of the unit cell lithium is 351 pm, the atomic radius of the lithium will be
240.8 pm
151.8 pm
75.5
75.5
AB crystallises in a body centred cubic lattice with edge length 'a' equal to 387 pm. The distance between two oppositely charged ion in the lattice is
335 pm
250 pm
200 pm
200 pm
Volume occipied by one molecule of water (density = 1 g cm-3) is
9.0 x 10-23
6.023 x 10-23 cm3
3.0 x 10-23 cm3
3.0 x 10-23 cm3
If 'a' stands for the edge length of the cubic system:simple cubic , body centred cubic and face centred cubic, then the ratio of radii of the spheres in these systems will be repsectively,
Percentage of free space in a body centred cubic unit cell is
30%
32%
34%
34%
Copper crystallises in a face-centered cubic lattice with a unit cell length of 361 pm. What is the radius of copper atom in pm?
128
157
181
108