Answer:
[tex]\frac{N_C}{N} = 1.42\times 10^{-4}[/tex]
Explanation:
given data:
temperature = 552 degree celcius = 825 Kelvin
energy for vacancy formation is given as 0.63 eV/atom
fraction of atom can be obtained from following formula
[tex]N_C = N e^{\frac{-Q_V}{kT}}[/tex]
Where, K IS BOLTZMAN CONSTANT [tex]= 8.62\times 10^{-5}eV/K[/tex]
[tex]\frac{N_C}{N} =e^{\frac{-0.63}{8.62\times 10^{-5} \times 825}[/tex]
[tex]\frac{N_C}{N} = e^{-8.8858}[/tex]
[tex]\frac{N_C}{N} = 1.42\times 10^{-4}[/tex]