Answers

2016-04-25T22:47:41+05:30
+5. The formula of phosphorus pentoxide is P2O5. (It should be called diphosphorus pentoxide but historically they got it wrong). O is -2 so P has to be +5

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2016-04-26T11:26:24+05:30
 The formula of phosphorus pentoxide is P2O5
therefore
 the valency of phosphorus in phosphorus pentoxide is 5+
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