## Gas Equilibrium Constant

Cynthia Tsang
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### Gas Equilibrium Constant

If given the reaction 2 NO2(g) + F2(g) <-> 2 FNO2(g) are the following equilibrium constants the same? If not, what are the differences and what units or information do you input into each one?
$K = \frac{[FNO_{2}]^{2}}{[F^{2}][NO_{2}]^{2}}$ vs. $K = \frac{[P_{FNO_{2})}]^2}{[P_{F_{2}}][P_{NO_{2}}]^2}$

Chem_Mod
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### Re: Gas Equilibrium Constant

The equilibrium constants are slightly different due to one being measured in terms of pressures and the other being measured in terms of concentrations. The constants are indeed related however: Kp = Keq*(RT)^(∆n), where ∆n is the moles of gaseous products - moles of gaseous reactants. The constants are both unitless.