Only those atoms which form four covalent bonds produce a repetitive three dimensional structure using only covalent bonds, e.g., diamond structure. The latter is based on an fcc lattice where four out of the eight tetrahedral holes are occupied by carbon atoms. Every atom in this structure is surrounded tetrahedrally by four others. Germanium, silicon and grey tin also crystallize in the same way as diamond ("Given " sin 54^(@) 44'=0.8164) Total number of unit cells in one gram of such sample is

Only those atoms which form four covalent bonds produce a repetitive t

1.	Only those atoms which form four covalent bonds produce a repetitive three dimensional structure using only covalent bonds, e.g., diamond structure. The latter is based on an fcc lattice where four out of the eight tetrahedral holes are occupied by carbon atoms. Every atom in this structure is surrounded tetrahedrally by four others. Germanium, silicon and grey tin also crystallize in the same way as diamond ("Given " sin 54^(@) 44'=0.8164) Total number of unit cells in one gram of such sample is
Answer» `4.95times10^(21)` `2.01times10^(22)` `6.27times10^(21)` `4.95times10^(22)` Solution :`(8times12)/(6.02times10^(23)) G " Present in one cell"` `therefore"total NUMBER of unit CELLS" = (6.02times10^(23))/(8times12)`.