An element crystallizes into a structure whichh may be described by a cubic layer of unit cell having one atom in each corner of the cube and two atoms on one of its face diagonals. If the volume of this unit cell is 24 xx 10^(-24) cm^(3) and density of the element is 7.20 gm//cm^(3), calcualte no. of atoms present in 200g of the element.

An element crystallizes into a structure whichh may be described by a

1.	An element crystallizes into a structure whichh may be described by a cubic layer of unit cell having one atom in each corner of the cube and two atoms on one of its face diagonals. If the volume of this unit cell is 24 xx 10^(-24) cm^(3) and density of the element is 7.20 gm//cm^(3), calcualte no. of atoms present in 200g of the element.
Answer» SOLUTION :Number of atoms contributed in onne unit CELL. = one atom from the eight corners = one atom from the two faces diagonals. =1+1=2 atoms. Mass of one unit cell = volume x its DENSITY `=24 xx 10^(-24) cm^(3) xx 7.2 gm cm^(3)` `=172.8 xx 10^(-24)` gm `therefore 172.8 xx 10^(-24) gm` is the mass of one - unit cell i.e., 2 atoms. `therefore 200` gm is the mass `=(2 xx 200)/(172.8 xx 10^(-24))` atoms `=2.3148 xx 10^(24)` atoms.