Question

Magnesium crystallises in the HCP structure with lattice constant a=3.21*10^10 and c/a ratio of 1.624. Determine
(a) The number of core electrons and the number of valence electrons in a Magnesium atom given that it has 12 electrons.
(b) The number density of (conduction) in the magnesium metal.

Answer 1

Answer:

1) Mg (12 electrons) has

2 electrons in shell 1 (a filled shell)

8 electrons in shell 2 (a filled shell)

2 electrons in shell 3 (incomplete).

Hence Mg has 10 core electrons and 2 valence electrons.

2) The conduction electron density is 

$n=Z_vρ_m/M$