Question

show that in a cubic close packed structure eight tetrahedral voids are present per unit cell .

Answer 1

cubic packed struture contains one atom at each corner of an unit cell and at force centre of ech unit cell Each unit cell consists of 8 small cubes.
Each small lead to creation of a tetrahedral void as shown below

since there are total 8 smaller cubes present at one unit cell each cubes has one tetrahedral void total number of tetrahedral void present in each unit cell is equal to right
As we known ccp struture has atoms per unit cell thus total number of tetrahedral void in one ccp unit cell equal to 8.