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Guilherme Mazui

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What is the Difference Between Monoprotic and Diprotic Acid?

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Monoprotic and diprotic acids differ in the number of hydrogen atoms or protons they can donate to their aqueous solutions. Here are the key differences between them:

  • Monoprotic Acids: These acids have only one ionizable hydrogen atom per molecule and can donate only one proton to their aqueous solution. Examples of monoprotic acids include hydrochloric acid (HCl), acetic acid (CH3COOH), and nitric acid (HNO3).
  • Diprotic Acids: These acids can donate two hydrogen atoms or protons to their aqueous solution. Examples of diprotic acids include sulfuric acid (H2SO4), carbonic acid (H2CO3), and oxalic acid (H2C2O4).

All acids, including monoprotic and diprotic acids, behave the same way by donating their proton(s) to other atoms. However, the number of acidic hydrogens in a molecule does not necessarily determine the acidity of the acid. For example, hydrochloric acid (monoprotic) is much stronger than phosphoric acid (triprotic), and sulfuric acid (diprotic) is much stronger than hydrofluoric acid (monoprotic).

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  • What is the Difference Between Monoprotic and Diprotic Acid?
  • Comparative Table: Monoprotic vs Diprotic Acid

    • Comparative Table: Monoprotic vs Diprotic Acid

    The main difference between monoprotic and diprotic acids lies in the number of protons they can donate. Here is a comparison table highlighting the differences:

    Feature Monoprotic Acids Diprotic Acids
    Definition Monoprotic acids have only one ionizable hydrogen atom per molecule. Diprotic acids have two ionizable hydrogen atoms per molecule.
    Examples HCl (hydrochloric acid), HF (hydrofluoric acid), HBr (hydrobromic acid), HNO3 (nitric acid). H2SO4 (sulfuric acid), H2S (hydrosulfuric acid), H2CO3 (carbonic acid).
    Strength Monoprotic acids can be strong or weak. Hydrochloric acid (HCl) is a strong monoprotic acid, while hydrofluoric acid (HF) is a weak monoprotic acid. Diprotic acids can also be strong or weak. Sulfuric acid (H2SO4) is a strong diprotic acid, while sulfurous acid (H2SO3) is a weak diprotic acid.
    Ionization Monoprotic acids lose only one proton during ionization. Diprotic acids lose two protons during ionization.

    It is essential to note that the acidity of an acid is not solely determined by the number of ionizable hydrogens. For example, hydrochloric acid (monoprotic) is stronger than phosphoric acid (triprotic), and sulfuric acid (diprotic) is stronger than hydrofluoric acid (monoprotic).

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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.