Silver crystallises with face-centred cubic unit cells. Each side of the unit cell has a length of 409 pm. Calculate the radius of silver atom. (Assume the atoms just touch each other on the diagonal across the face of the unit cell. That is each face atom is touching the four corner atoms.)

Explanation

For fcc unit cell
`r = (a)/(2 sqrt(2))`
Given, a = 400 pm
`r = 400//2 sqrt(2)` pm
r = 141.4 pm