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Guilherme Mazui

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What is the Difference Between Phosphorus and Phosphoric Acid?

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Phosphorus and phosphoric acid are both compounds containing the chemical element phosphorus (P), but they have different chemical properties and uses. The key differences between them are:

  1. Oxidation State: Phosphorous acid (H3PO3) is a partially oxidized and hydrated form of phosphorus, while phosphoric acid (H3PO4) is a fully oxidized and hydrated form of phosphorus.
  2. Protonation: Phosphorous acid is diprotic, meaning it can release two protons when in an aqueous solution, while phosphoric acid is triprotic, meaning it can release three protons when in an aqueous solution.
  3. Uses: Phosphoric acid is a nutrient source of phosphorus essential for plant growth, while phosphorous acid helps control agricultural epidemics of oomycetes.

In summary, phosphorous acid and phosphoric acid are both phosphorus-containing acids with distinct chemical properties and functions. Phosphorous acid is a partially oxidized and diprotic form of phosphorus, while phosphoric acid is a fully oxidized and triprotic form of phosphorus.

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  • What is the Difference Between Phosphorus and Phosphoric Acid?
  • Comparative Table: Phosphorus vs Phosphoric Acid

    • Comparative Table: Phosphorus vs Phosphoric Acid

    The following table highlights the differences between phosphorus and phosphoric acid:

    Property Phosphorus (Phosphonic Acid, H3PO3) Phosphoric Acid (Trihydroxidooxidophosphorus, H3PO4)
    Acidity Diprotic Acid Triprotic Acid
    Protons Released 2 3
    Uses Production of basic lead phosphite (a stabilizer in PVC) Fertilizers, dental cements, albumin derivatives, sugar and other food products
    Production Process Made via hydrolysis of the anhydride of the acid (P4O6) or by hydrolysis of phosphorous chloride (PCl3) with steam Made via wet process or thermal process
    pH Less acidic compared to phosphoric acid More acidic than phosphorous acid

    Please note that the acidity of phosphorous acid (H3PO3) is less than that of phosphoric acid (H3PO4), making it less acidic. Both acids are used in various industries, with phosphorous acid being a diprotic acid and phosphoric acid being a triprotic acid, meaning they can release 2 and 3 protons, respectively.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.