KCET2020ChemistrySolid State
A metal crystallises in face centred cubic structure with metallic radius 2 Å . The volume of the unit cell (in m ³ ) is
Options
- A4 10⁻¹⁰
- B6.4 10⁻²⁹
- C4 10⁻⁹
- D6.4 10⁻³⁰
Correct answer
B. 6.4 10⁻²⁹
Step-by-step solution
In fcc, 4 r= 2 a aligned Volume of unit cell &=a³= ( 4 r 2 )³= 64 2 2 ( 2 )³ Å &= 64 2 2 2 2 Å &=64 10⁻³⁰ ~m ³ &=6.4 10⁻²⁹ ~m ³ aligned