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How will you prepare phosphine and explain the purification of phosphine? |
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Answer» Solution :Phosphine is prepared by action of sodium hydroxide with white phosphorous in an inert ATMOSPHERE of carbon of hydrogen. `P_(4)+3NaOH+3H_(2)Orarr underset("sodium hypo phosphite")(3NaH_(2)PO_(2))+underset("Phosphine")(PH_(3)uarr)` Phosphine is freed from phosphine DIHYDRIDE `(P_(2)H_(4))` by passing through a freezing mixture. The dihydride condenses while phosphine does not. Phosphine can also prepared by the hydrolysis of METALLIC phosphides with water of dilute mineral acids. `Ca_(3)P_(2)+6H_(2)Orarr underset("Phosphine")(2PH_(3)uarr)+3Ca(OH)_(2)` `AlP+3HClrarr underset("Phosphine")(PH_(3)uarr)+AlCl_(3)` Phosphine is prepared in pure form by heating phosphorous acid. `underset("Phosphorous acid")(4H_(3)PO_(3))overset(Delta)RARR underset("Ortho phosphoric acid")(3H_(3)PO_(4))+underset("Phosphine")(PH_(3)uarr)` A pure sample of phosphine is prepared by heating phophonium iodide with caustic soda solution. `PH_(4)I+NaOH overset(Delta)rarr underset("Phosphine")(PH_(3)uarr)+NaI+H_(2)O` |
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