Question

Volume of unit cell occupied in face-centered cubic arrangement is ____________.

Options

• 100%

• 52.35%

• 74%

• 68%

Answer 1

Volume of unit cell occupied in face-centered cubic arrangement is 74%.

Explanation:

Packing efficiency = `("Volume occupied by four shares in the unit cell" xx 100)/("Total volume of the unit cell")%`

= `(4 xx (4/3)π"r"^3 xx 100)/(2sqrt2"r")^3%`

= `((16/3)π"r"^3 xx 100)/(16sqrt2"r"^3)%`

= 74%