The free energy of formation of nitric oxide, NO, at 1000 K (roughly the temperature in an automobile engine during ignition) is about 78 kJ/mol. Calculate the equilibrium constant Kp for the reaction N2(g) + O2(g) 2NO(g) at this temperature.

Respuesta :

Answer: The value of [tex]K_p[/tex] for the chemical equation is [tex]8.341\times 10^{-5}[/tex]

Explanation:

For the given chemical equation:

[tex]N_2(g)+O_2(g)\rightarrow 2NO(g)[/tex]

To calculate the [tex]K_p[/tex] for given value of Gibbs free energy, we use the relation:

[tex]\Delta G=-RT\ln K_p[/tex]

where,

[tex]\Delta G[/tex] = Gibbs free energy = 78 kJ/mol = 78000 J/mol  (Conversion factor: 1kJ = 1000J)

R = Gas constant = [tex]8.314J/K mol[/tex]

T = temperature = 1000 K

[tex]K_p[/tex] = equilibrium constant in terms of partial pressure = ?

Putting values in above equation, we get:

[tex]78000J/mol=-(8.314J/Kmol)\times 1000K\times \ln K_p\\\\Kp=8.341\times 10^{-5}[/tex]

Hence, the value of [tex]K_p[/tex] for the chemical equation is [tex]8.341\times 10^{-5}[/tex]

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