The density of solid cr is 7.15 g/cm3. how many atoms are present per cubic centimeter of cr?
as a solid, cr adopts a body-centered cubic unit cell. how many unit cells are present per cubic centimeter of cr?

For a body centered cubic unit cell, it is known that there will be two atoms per unit cell. For the number of unit cells per cubic centimeter, we do as follows:

( 7.15g / 1 cm³ ) x ( 1 mol / 52.00g) x (6.022x10^23 atoms / 1 mole ) x ( 1 unit cell / 2 atoms) = 4.14 x 10^22 units cells / cm^3

Hope this answers the question. Have a nice day.

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