Estimate the volume of an atom of iron 56Fe given atomic number: 26

A.) 8.6 x 10-24 cc
B.) 1.2 x 10-23 cc
C.) 2.4 x 1024 cc
D.) 3.6 x 1024 cc

Those two numbers will not help you compute the atomic volume.

Instead, look up the density of solid iron. It is 7.86 g/cm^3. Each atom has a mass of 56 (g/mole)/Navogadro = 9.3*10^-23 g/atom

The number of atoms per cm^3 is therefore 8.45*10^22

Each Fe atom occupies a volume (in a cubic array) of (8.45*10^22)^-1 =

1.18*10^-23 cm^3

That is pretty close to choice (B)