A certain element crystallises in a bcc lattice of unit cell edge length 27 Å. If the same element under the same conditions crystallises in the fcc lattice, the edge length of the unit cell in Å will be ____. (Round off to the nearest Integer).
[Assume each lattice point has a single atom]
[Assume √3=1.73, √2=1.41]
[Assume each lattice point has a single atom]
[Assume √3=1.73, √2=1.41]
Answer: 33
Solution
The same element under the same conditions keeps the same atomic radius in both lattices.
In a body-centred cube the atoms touch along the body diagonal, so and
In a face-centred cube they touch along the face diagonal, so and
Rounded to the nearest integer, the edge length of the face-centred cubic cell is 33 Å.
In a body-centred cube the atoms touch along the body diagonal, so and
In a face-centred cube they touch along the face diagonal, so and
Rounded to the nearest integer, the edge length of the face-centred cubic cell is 33 Å.
JEE Main · 2021 · 16 Mar 2021 · Shift 1 · Integer answer