Pyrophosphoric acid contains only one P-O-P bonds.
Pyrophosphate is the conjugate base of Pyrophosphoric Acid and is corrosive as well as toxic in nature. Pyrophosphoric Acid is a medium-strong inorganic hygroscopic by nature and is a colourless as well as odourless chemical. Anions, salts, and esters of pyrophosphoric acid are called pyrophosphates. The structural formula of Pyrophosphoric Acid is as shown in the figure below.