NEET2008ChemistrySolid StateActual
Which of the following statements is not correct?
Options
- AThe fraction of the total volume occupied by the atoms in a primitive cell is 0.48
- BMolecular solids are generally volatile
- CThe number of carbon atoms in an unit cell of diamond is 4
- DThe number of Bravais lattices in which a crystal can be categorized is 14
Correct answer
A. The fraction of the total volume occupied by the atoms in a primitive cell is 0.48
Step-by-step solution
Key Idea: Packing fraction of lattice structure or fraction of total volume occupied = Volume occupied by atoms in a unit cell Volume of the unit cell Packing fraction of simple cube gathered = 1 4 3 r^3 a^3 = 1 4 3 r^3 (2 r)^3 =0.52 gathered ( For primitive cell a=2 r ) Volume occupied =52 %