Chemistry
posted by Lauren .
what is the volume of the unit cell?
A metal crystallizes in a facecentered cubic lattice. The radius of the atom is 0.197 nm. The density of the element is 1.54 g/cm^3

And the question is?? And tell us what you don't understand about it.

The question is what is the volume of the unit cell?
I don't understand how to get the volume of it 
The diagonal along the face of the crystal for a fcc is 4r. Since you know the radius you can calculate the length of the diagonal. Remember that the diagonal of a right triangle in which the sides are equal is a^2 + a^2 = (diagonal)^2 which allows you to calculate a, the edge of the cell. Then a^3 is the volume. Post your work if you get stuck.