Silver crystallises with face centred cubic unit cells. Each side of the unit cell has a length of 409 pm. What is the radius of an atom of silver ? (Assu!'le that each face atom is touching the four corner atoms)

Explanation

We are given that
`a=409 pm`
`r=?`
For the face centred cubic unit cell
`d=a/(sqrt2)=409/1.414=289.25pm,r=d/2=(289.25)/2=144.6pm`