Question

If a metal with atomic mass 209 crystallizes in a simple cubic lattice what is the edge length of its unit cell. (Given d = 91.5 kg m^-3).

Answer 1

As we know,

density 'd' = \(\frac{ƵM}{a^3N_A}\)

a³ = \(\frac{1\times209 g/mol}{6.022\times10^{23}\times91.5 \times 10^3 g/m^3}\)

a³ = 0.3793 x 10^-26 m³

a³ = 3.793 x 10^-27 m³

a = 1.5595 x 10^-9 m

a = 1.56 x 10^-9 m