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50 Questions around this concept.
In a molecule of pyrophosphoric acid, the number of P-OH, P = O, and P – O – P bonds/moiety (ies) respectively are :
Orthophosphoric acid is -
Which of the following statements is not valid for oxoacids of phosphorus?
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Strong reducing behaviour of $\mathrm{H}_3 \mathrm{PO}_2$ is due to:
The number of P−OH bonds and the oxidation state of phosphorus atom in pyrophosphoric acid (H4P2O7) respectively are :
The pair that contains two P-H bonds in each of the oxoacids is :
Oxidation number of P in $\mathrm{PO}_4^{3-}$, of S in $\mathrm{SO}_4^{2-}$ and that of $\mathrm{Cr}_2 \mathrm{O}_7^{2-}$ are respectively
Which of the Phosphorus oxoacid can create silver mirror from solution?
The number of lone pair on phosphorus in phosphorus acid is :
Which acid is tribasic
Phosphorus forms a number of oxoacids. The important oxoacids of phosphorus with their formulas, methods of preparation and the presence of some characteristic bonds in their structures are given in Table given below.

The compositions of the oxoacids are interrelated in terms of loss or gain of H2O molecule or O-atom. The structures of some important oxoacids are given in later pictures. In oxoacids phosphorus is tetrahedrally surrounded by other atoms. All these acids contain at least one P=O bond and one P–OH bond. The oxoacids in which phosphorus has lower oxidation state (less than +5) contain, in addition to P=O and P–OH bonds, either P–P (e.g., in H4P2O6) or P–H (e.g., in H3PO2) bonds but not both. These acids in +3 oxidation state of phosphorus tend to disproportionate to higher and lower oxidation states. For example, orthophophorous acid (or phosphorous acid) on heating disproportionates to give orthophosphoric acid (or phosphoric acid) and phosphine.
The structures of some Oxoacids of Phosphorus are given below :

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