Face centered cubic question

Oct 2016
10
0
The atomic radius of metal X is 1.50 × 102 picometers (pm) and a crystal of metal X has a unit cell that is face-centered cubic. Calculate the density of metal X (atomic weight = 42.3 g/mol).
 

topsquark

Forum Staff
Jul 2013
56
1
Any place where Alyson Hannigan can find me
The atomic radius of metal X is 1.50 × 102 picometers (pm) and a crystal of metal X has a unit cell that is face-centered cubic. Calculate the density of metal X (atomic weight = 42.3 g/mol).
The main concept here is to find the density of the material...ie. from a single unit cell. So for an FCC crystal how many atoms of X are in the unit cell? What are the dimensions of the unit cell? So now you know the density in terms of # of atoms/volume in a unit cell. The rest is unit conversions.

Does this help or do you need more?

-Dan
 
Jan 2019
12
2
India
We know that σ = (Z × M)/(N × a³)

Here, Z = 4 for fcc cubic Crystal, M = 42.3 gm/mol and N = 6.023 × 10²³ and a = 1.50 × 10² pm = 1.50 × 10⁻⁸ cm

Putting the value on the above equation to calculate the density of the crystal X.
 
Similar Chemistry Discussions Chemistry Forum Date
High School Chemistry
Undergraduate Chemistry