In a gas-phase equilibrium mixture of SbCl 5 , SbCl 3 and Cl

In a gas-phase equilibrium mixture of SbCl5, SbCl3 and Cl2at 500 K, the partial pressures of SbCl5 and SbCl3 are 0.18bar and 0.22 bar, respectively. Given that KP=3.5 x 10-4 for the reaction
SbCl5(g)=SbCl3(g) + Cl2(g),
what is the equilibrium partial pressure of Cl2 in bars? Enter only the numeric part of the answer to an accuracy of 0.00001, not the units.
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