Chemistry
posted by ChemLover .
Silver crystallizes in a face centered cubic unit cell with an edge length of 0.40836 nm. Calculate the density of silver in grams per cubic centimeter
i know the answer is 10.5 g/cm^3 but i keep getting lost in figure it out.

mass of mole Ag atoms = 107.868. Mass of 1 atom = 107.868/6.022E23 = ??
?? x 4 atoms/unit cell = mass unit cell in grams.
Then density = grams/volume where volume = (0.40836E7 cm)^3
I obtained 10.52 g/cc. 
for some reason i keep getting 2.63
i got 1.79 x 10^22 g / 6.823 x 1023 cm^3
and i keep getting 2.63...what an i doing wrong??? 
ohhhh never mind i forgot to multiply by 4....thank you