# Question #fde10

##### 1 Answer

#### Explanation:

**1. Calculate the volume of the unit cell**

Convert pm to cm

1 pm =

419 pm =

Volume of unit cell =

Volume of unit cell =

**2. Determine the mass of the metal in the unit cell**

Mass of metal in unit cell =

Mass of metal in unit cell =

**3. Determine number of atoms per unit cell**

We have face-centered unit cell:

Lattice points on the corner count for an 1/8 because they are shared with 8 other unit cells. Lattice points on the face count for 1/2 as they are shared with one other unit cell.

1/8 x 8 corners = 1 lattice point

1/2 x 6 faces = 3 lattice points

Total number of lattice points (atoms) per unit cell = 4

**4. Calculate molar mass of unknown metal**

Mass per atom = Total mass of metal in unit cell / number of atoms in unit cell

Mass per atom =

Mass per atom =

Use mass to determine molar mass by multiplying by Avogadro's number:

molar mass =

molar mass =

Looking at the periodic table, this molar mass is the closest to radon.