Solid State Tes...

If a is the lattice parameter, the volume of an fcc crystal having $$N$$ atoms is :

The physical dimension of unit cells in a crystal lattice:

If A is the molecular mass of an element, a is the edge length and $$N$$ is the Avogadro's number, then the density for simple cubic lattice is :

The lattices of Na and Al are bcc and fcc respectively. Presuming them to be closed packed, their packing fractions are, respectively :

The density of solid argon (atomic mass $$=40$$ amu) is $$1.68$$ g/ml at $$40$$ K. If the argon atom is assumed to be a sphere of radius $${1.50 \times 10^{-8}}$$ cm, then the percentage of solid Ar which is space will be: 

An atomic solid crystallizes in a body centre cubic lattice and the inner surface of the atoms at the adjacent corner are separated by $$60.3$$ pm. If the atomic weight of A is $$48$$, then the density of the solid is nearly:

The packing efficiency of a simple cubic crystal with an interstitial atom exactly fitting at the body center is:

Sodium (atomic mass $$=23$$ amu) crystallizes in a bcc arrangement with the interfacial separation between the atoms at the edge $$53.6$$ pm. The density (in g cm$$^{-3}$$) of sodium crystal is:

If A is the molecular mass of an element, a is the edge length and $$N$$ is the Avogadro's number, then the density for face-centered cubic lattice is :

Packing fraction in face-centered cubic unit cell is :