What is the percent dissociation of 0.20 M iodic acid? (The K_a value for iodic acid, HIO₃, is 1.7 *10^-1.)

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The percent dissociation of a weak acid can be calculated using the following equation:% dissociation = ( [H+] / [HA] ) x 100%where [H+] is the molar concentration of hydrogen ions and [HA] is the molar concentration of the weak acid.For iodic acid, the Ka value is 1.7 x 10^-1. This means that the equilibrium constant for the dissociation of iodic acid is 1.7 x 10^-1.The equilibrium constant expression for the dissociation of iodic acid is:Ka = [H+][IO3-] / [HIO3]Substituting the Ka value and the initial concentration of iodic acid (0.20 M) into the equilibrium constant expression, we get:1.7 x 10^-1 = [H+][IO3-] / 0.20 MSolving for [H+], we get:[H+] = 3.4 x 10^-2 MNow we can calculate the percent dissociation:% dissociation = ( [H+] / [HA] ) x 100%% dissociation = ( 3.4 x 10^-2 M / 0.20 M ) x 100%% dissociation = 17%Therefore, the percent dissociation of 0.20 M iodic acid is 17%.

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