A metallic element crystallises in simple cubic lattice. If edge legth of the unit cell is 3 A^ , with density 8 ~g / cc , what is the number of unit cells in 100 ~g of the metal? ( Molar mass of metal =108 ~g / mol )

Step-by-step solution

( B ) a =3 Å=3 10⁻⁸ ~cm Volume of the unit cell ( a ³ )= (3 10⁻⁸ )³ ~cm ³=27 10⁻²⁴ ~cm ³ Mass of unit cell =27 10⁻²⁴ ~cm ³ 8 ~g ~cm ⁻³=216 10⁻²⁴ ~g aligned 216 10⁻²⁴ ~g =1 unit cell & 108 ~g =& 108 216 10⁻²⁴ =5 10²³ unit cells. aligned