If the oxoacid, ${\mathrm{H}}_4{\mathrm{P}}_2{\mathrm{O}}_6$ contains$\mathrm{P}-0-\mathrm{P}$ linkage, find the difference in oxidation state of two phosphorus atoms.

The oxidation state on the two phosphorous atoms are +5 and +3 as show in the molecular geometry.

 The difference in oxidation state of two phosphorus atoms is,

$$\begin{gathered} =+5-(+3) \\ =2 \end{gathered}$$