posted by Anna .
An element crystallizes in a body-centered cubic lattice. The edge of the unit cell is 3.5 Angstrom, and the density of the crystal is 7.39g/cm^3. Calculate the atomic weight of the element. A= ? g/mol
The bcc has two atoms/unit cell.
The edge is 3.5 x 10^-8 cm = a
Volume = a3 = 3.5 x 10^-8)^3 cc
mass = volume x density
mass = a3 x 7.49 g/cc = xx
2atoms/unit cell x atomic mass/6.022 x 10^23 = xx mass
Solve for atomic mass.
I made a typo. The density is 7.39, not 7.49 g/cc.