Missing question: Assume a density of 10.35 g/cm3 for Ag, A(Ag) = 107.87 g/mol.
N(Ag) = Na · d(Ag) ÷ A(Ag).
N(Ag) = 6,023·10²³ atoms/mol · 10,35 g/cm³ · 10⁶ cm³/m³ ÷ 107,87 g/mol.
N(Ag) = 5,78·10²⁸ atoms/mol.
Nv = 5,78·10²⁸ atoms/mol · 5·10⁻⁵.
Nv = 2,89·10²².