An element has a body-centred cubic (bcc) structures with a cell edge of 444 pm. The density of the element is 7.2 g/cm3. How many atoms are present in 404 g of the element?

Volume of the unit cell = (444 pm)₃ 3 12 444 10 m x 3 10 444 10 cm x 23 3 8.75 10 cm x Volume of 404 g of the element 3 Mass 404 Density 7.2g cm 3 56.11cm ∴ Number of unit cells in this volume 23 3 56.11 8.75 10 cm / unit cell x 23 6.41 10 x unit cells