The reaction between phosphorus (P) and chlorine (Cl2) can produce phosphorus trichloride (PCl3) or phosphorus pentachloride (PCl5), depending on the reaction conditions and the stoichiometry.
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Phosphorus Trichloride (PCl3): \[ P + 3Cl_2 \rightarrow PCl_3 \] In this reaction, one atom of phosphorus reacts with three molecules of chlorine gas to produce one molecule of phosphorus trichloride.
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Phosphorus Pentachloride (PCl5): \[ P + 5Cl_2 \rightarrow PCl_5 \] Here, one atom of phosphorus reacts with five molecules of chlorine gas to form one molecule of phosphorus pentachloride.
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