Copper has a face-centered cubic unit cell. the density of copper is 8.96 g/cm3. calculate a value for the atomic radius of copper.

Given That copper has a face centered cubic unit cell. that is, copper is present on the corners and the face center. Thus, the number of Cu atoms in one unit cell is 4.
For FCC, the relation between edge length and radius of atom is given as follows:
a = 2 √2r
Here, a is the edge length and r is the radius of copper atom.
The density of the unit cell is 8.96 g/cc. Density can be calculated as follows:
d = 
Here, d is the density of the unit cell, Z is the number of Cu atoms in the unit cell, M is the molar mass of copper,  is Avogadro's number, and a is the edge length.
Substitute the expression for a as shown below:
d = 
d = 

8.96 g / = 

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf   

Theoretical temperature at which molecules stop moving and no more heat can be removed from the object. kelvin: absolute zero degrees. none of the above.