Why is PCl3 acidic? [closed]








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Why is it that when adding PCl3 into distilled water, the solution becomes acidic? What exactly is the reaction occurring? Must it not be neutral as the PCl3 is molecular, or then P has a lone pair of electrons, so is it not a Lewis base?




According to this source  [here](https://www.baylor.edu/ehs/index.php?id=93803)



> 
> Phosphorus trichloride (phosphorus chloride, PCl3) is a colorless fuming liquid that reacts violently with water to liberate phosphorous acid (H3PO3) and hydrogen chloride (HCL) gas.
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The oxygen of water attacks the P atom, which is positively polarised because of the 3 electronegative chlorines attached to it.


The HCl gas dissolves in the water to give hydrochloric acid so the resulting solution contains 2 strong acids.


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