+1 vote
50 views

A certain element crystallises in a bcc lattice of unit cell edge, length 27ºÅ. If the same element under the same conditions crystallises in the fcc lattice, the edge length of the unit cell in Å will be………. (Assume each lattice point has a single atom)

[Assume $$\sqrt3 = 1.73, \sqrt2 = 1.41$$]

in random
reopened | 50 views

Explanation::

for bcc structure $$4r=\sqrt3a$$

$$r={\sqrt3a\over4}$$   …1

For FCC structure $$4r=\sqrt2a$$

$$r={\sqrt2a\over4}$$ …2

From 1 and 2

by Expert (11.1k points)