Question

what is the number of each atom in the unit cell of a BCC cystalline structure unit cell.

I know its 2 atoms=8/8 +1

Calculate what % of each atom is contained within the unit cell?
How do I do this

Answer 1

This is math??
Yes, there are two atoms/unit cell in a bcc.
I don't know how much information you have but the general idea is to calculate the volume of the unit cell (vol = mass/density), then calculate the volume of the two atoms [(4/3)*pi*r^³ for each of the two atoms]. then divide
(vol sphere/vol unit cell)*100 = percent occupied by atoms.