GEOLOGY

Detailed explanation-1: -The atomic packing fraction for the FCC crystal structure is 0.74. This is the densest arrangement of atoms achievable in three dimensions when all atoms have the same radius R. If atoms in the hard sphere model occupy 74% of the volume of the unit cell, then the other 26% is empty space.

Detailed explanation-2: -The atomic packing factor is defined as the ratio of the volume occupied by the average number of atoms in a unit cell to the volume of the unit cell. for FCC a = 2√2 r where a is side of the cube and r is atomic radius. The Union Public Service Commission has released the UPSC IES Prelims Admit Card on 27th Jan 2023.

Detailed explanation-3: -The means 74% of the total volume within a face-centred cubic unit cell is occupied by the constituent particles of the unit cell. Step by step solution by experts to help you in doubt clearance & scoring excellent marks in exams.

Detailed explanation-4: -For fcc and hcp structures, the atomic packing factor is 0.74, which is the maximum packing possible for spheres all having the same diameter.

Detailed explanation-5: -Solution : The packing fraction or the volume of occupied space in f.c.c. packing is 0.74 (or ‘74%‘).