Answer:
The edge length of a face-centered cubic unit cell is 435.6 pm.
Explanation:
In a face-centered cubic unit cell, each of the eight corners is occupied by one atom and each of the six faces is occupied by a single atom. 
Hence, the number of atoms in an FCC unit cell is:

In a face-centered cubic unit cell, to find the edge length we need to use Pythagorean Theorem:
 (1)
     (1)
Where:
a: is the edge length 
R: is the radius of each atom = 154 pm      
By solving equation (1) for "a" we have:
 
    
Therefore, the edge length of a face-centered cubic unit cell is 435.6 pm.    
I hope it helps you!
 
        
             
        
        
        
N2H4
<span>Each nitrogen weighs 14.01 and each H weighs 1.01. !4.01+14.01+1.01+1.01 = 32.06 (roughly) </span>
        
                    
             
        
        
        
A scientific theory is a well tested explanation of a natural phenomenon.
        
             
        
        
        
The molar mass of magnesium hydroxide is 58.3197 g/mol.