3D-packing#!#Density of cell

in the cubic packing , the unit cell has ………. .

In the cubic close close packing, the unit cell has....

Assertion :The close packing of atoms in cubic structure is in the order fcc gt bcc gt sc Reason: Packing density = ("Volume of unit cell")/(a^(3))

Assertion (A) : Packing efficiency in simple cubic unit cell is 52.4% . Reason (R) : Density of the unit cell is given by the relation : d=(a^(3)N_(A))/(ZM) .

The packing efficiency of the 2D square unit cell shown below is

The packing efficiency of the two dimensional square unit cell shown is :