A metal crystallizes into two cubic phases, face centered cubic (fcc) and body centered cubic (bcc), whose unit cell lengths are 3.5 A° and 3.0 A°, rcspcctively. Calculate the ratio of densities of fcc and bcc. (IIT-JEE 1999)

The ratio of the densities of fcc to bcc is

A metallic element crystallizes into a lattice containing a sequence of layers ABABAB....Any packing of spheres leaves out voids in the lattice. What percentage by volume of this lattice is empty space? ( IIT-.IEF 2006)

The sequence ABABAB... indicates hcp unit cell. Now, there are 6 atoms per unit cell and volume of the umt cell is 24√2 r3.Thus, the packing fraction is:

The coordination number of Al in the crystalline state of AlCl3 is .... (IIT-JEE 2009)

AlCl3 exist in CCP unit cell with 6 co-ordinate layer structure and coordination number of Al is (6)

The number of hexagonal faces that are present in truncated octahedron is .... (IIT-JEE 2011)

The number of hexagonal faces that are present in truncated octahedron is  (6) this can seen if given fig.

In Diamond Carbon atom occupie FCC lattice point as well as alternate tetrahedral voids. If edge length of unit cell is 3.56 pm the find the radius of carbon atom is.