Calculate the percent ionization of formic acid (HCO₂H) in a solution that is 0.311 M in formic acid and 0.189 M in sodium formate (NaHCO₂). The K_aof formic acid is 1.77 ×10^-⁴. A) 0.0952 B) 1.06 × 10^-³ C) 11.3 D) 3.529 E) 37.8

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First, we need to write out the balanced chemical equation for the dissociation of formic acid: HCO₂H ⇌ H+ + CO₂- Next, we can use the given equilibrium constant (Ka) and the initial concentrations of formic acid and sodium formate to set up an ICE table: HCO₂H ⇌ H+ + CO₂- I 0.311 M 0 M 0 M C -x +x +x E 0.311-x x x The Ka of formic acid is equal to [H+][CO₂-]/[HCO₂H]. Substituting the equilibrium concentrations into this expression gives: 1.77 ×10^-⁴ = x^2 / (0.311 - x) We can make the assumption that x is much smaller than 0.311, so we can approximate 0.311 - x to be approximately 0.311: 1.77 ×10^-⁴ = x^2 / 0.311 Solving for x gives x = 0.0295 M. The percent ionization is equal to (x / 0.311) x 100%. Plugging in our calculated value for x gives: Percent ionization = (0.0295 / 0.311) x 100% = 9.52% Therefore, the best choice is A, 0.0952, as it is the closest value to our calculated value of 9.52%.

Calculate the Percent Ionization of Formic Acid (HCO2H) in a Solution

Calculate the Percent Ionization of Formic Acid (HCO₂H) in a Solution