Answer
$\frac{N_{v}}{N} = 4.56 \times 10^{-4}$
Work Step by Step
Given:
Copper with melting temperature of 1084°C (1357K)
energy of vacancy formation is 0.90 eV/atom
Required:
fraction of atom sites that are vacant
Solution:
Using Equation 4.1:
$\frac{N_{v}}{N} = exp (-\frac{Q_{v}}{kT}) = exp (-\frac{0.90 eV/atom}{(8.62 \times 10^{-5} eV/atom-K)(1357 K)} )= 4.56 \times 10^{-4}$
