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Phosphorus pentachloride decomposes at higher temperatures. PCl5(g)PCl3(g)+Cl2(g) An equilibrium mixture at some temperature consists of 4.42gPCl5,208.23g/mol 4.86gPCl3,137.33g/mol 3.59gCl2,70.91g/mol in a 1.00-L flask. If you add 1.31g of Cl2, how will the equilibrium be affected and what will the concentration of PCl5 be when equilibrium is reestablished? shift left shift right no shift will occur