Phosphonic acid

This article is about the group of chemicals. For the specific chemical also called phosphonic acid, see phosphorous acid.

"Phosphonate" redirects here. For the ion systematically named phosphonate, see phosphite.

Phosphonic acids are a type of organic compound that has phosphorus. They have the functional group −PO(OH)₂. They are derivatives of phosphorous acid (HPO(OH)₂) that replace the single hydrogen atom with the organic part of the molecule. "Phosphonic acid" is also another name for phosphorus acid. Salts and esters of phosphonic acids are called phosphonates.