BITSAT2016ChemistrySolid StateActual
Al (at. wt 27 ) crystallizes in the cubic system with a cell edge of 4.05 Ã… . Its density is 2.7 ~g per cm ³ . Determine the unit cell type calculate the radius of the Al atom
Options
- Afcc , 2.432 Ã
- Bbcc, 2.432 Ã
- Cbcc, 1.432 Ã
- Dfcc , 1.432 Ã
Correct answer
D. fcc , 1.432 Ã
Step-by-step solution
= Z M N₀ a³ , 2.7= Z 27 6.02 10²³ (4.05)³ 10⁻²⁴ Z=4 Hence it is face centred cubic unit lattice. Again 4 r=a 2 =5.727 Ã… r =1.432 Ã…