Question
Question: A metallic elements exists as a cubic lattice. Each edge of the unit cell is 2.88*Å*. The density of...
A metallic elements exists as a cubic lattice. Each edge of the unit cell is 2.88Å. The density of the metal is 7.20 gcm−3. How many unit cells will be present in 100 gm of the metal.
A
5.82 ×1023
B
6.33×1023
C
7.49×1024
D
6.9×1024
Answer
5.82 ×1023
Explanation
Solution
The volume of unit cell (V) = a3 = (2.88Å)3
= 23.9×10−24cm3
Volume of 100 g of the metal = DensityMass=7.20100=13.9cm2
Number of unit cells in this volume = 23.9×10−24cm313.9cm3=5.82×1023