Phosphoric acid is a polyprotic acid. Write balanced chemical equations for the sequence of reactions that phosphoric acid can undergo when it's dissolved in water is given below
Explanation:
Many acids contain two or more ionizable hydrogens. There are two in carbonic acid, H₂CO₃, and three in phosphoric acid, H ₃PO ₄. For any such multiple hydrogen acid, the first hydrogen is most easily removed, and the last hydrogen is removed with the greatest difficulty. These acids are called polyprotic (many protons) acids. The multiple acid ionization constants for each acid measure the degree of dissociation of the successive hydrogens.
Step 1
Polyprotic acid is an acid that can donate two or more H+ ion per molecule. Sulfurous acid donates two hydrogen ions in an aqueous solution.
Step 2
Dissociation of sulfurous acid in aqueous solution takes place in two steps. In the first step, one H⁺ ion is donated during dissociation forming HSO₃⁻.
H₂SO₃₍aq₎ +H₂O₍₁₎→HSO₃⁻₍aq₎
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Step 3
In the second step, one H+ ion is donated from HSO3- ion f...
H₂SO₃₍aq₎ +H₂O₍₁₎→SO₃²⁻₍aq₎+H₃O⁺₍aq₎