Phosphorous acid dissociates to form dihydrogen phosphite and hydronium ion. Phosphorous acid has Ka of 5.0 x 10-2.
Write the equation dissociation for phosphorous acid. Express your answer as a chemical equation. Identify all of the phases in your answer.
What is the expression constant dissociation for phosphorous acid?
a) Ka = [H2PO3-] / [H3PO3]
b) Ka = [H3PO3] / [H3O+][H3PO3-]
c) Ka = [H3O+][H2PO3-] / [H3PO3]
d) Ka = [H3O+] [H2PO3-] / [H3PO3]2
First, write the dissociation reaction. We start with the acid and water (solvent) as the reactants. Then the products should be the conjugate base (1 less H) and H3O+ ( where the H went). Take note of the charges. The conjugate base should gain a negative charge. All of the compounds except water (liquid) should be aqueous (aq) since they are dissolved in water.