1. The density of solid Cu is 8.96g/cm3. How many atoms are present per cubic centimeter (cm3) of Cu?

2. As a solid, Cu adopts a face‑centered cubic unit cell. How many unit cells are present per cubic centimeter (cm3) of Cu?

3. What is the volume of a unit cell of this metal? What is the edge length of a unit cell of Cu?

8.5 * 10²² atom / cm³, 2.125 * 10²² unit cells / cm³, 4.7 * 10⁻²³ cm³ / cell unit, 3.61 * 10⁻⁸ cm / cell

Explanation:

The density of the solid Cu = 8.96 g/cm³

a) number of atoms present

mole = mass / molar mass = (8.96 g/cm³) / 63.546 = 0.141 mol

number of atoms = mole * avogadro's constant = 0.141 * 6.02 * 10²³ = 8.5 * 10²² atom / cm³

b) a face-centered cubic unit cell contains 4 atoms

8.5 * 10²² atom / cm³ / 4 = 2.125 * 10²² unit cells / cm³

c) the volume of a unit cell of the metal = reciprocal of 2.125 * 10²² unit cells / cm³ = 1 : (2.125 * 10²² unit cells / cm³) = 4.7 * 10⁻²³ cm³ / cell unit

the edge length of a cell of cu = ∛ (4.7 * 10⁻²³ cm³ / cell unit) = 3.61 * 10⁻⁸ cm / cell