Calculate the concentration of bicarbonate ion, HCO₃^-, in a 0.0 10 mol L^-1 H₂CO₃ solution that has the stepwise dissociation constants K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11. A) 6.6 × 10^-⁵ mol L^-1 B) 4.3 × 10^-7 mol L^-1 C) 4.3 × 10^-⁹ mol L^-1 D) 5.6 × 10^-11 mol L^-1

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The correct answer is A because the concentration of bicarbonate ion, HCO₃^-, in a 0.0 10 mol L^-1 H₂CO₃ solution that has the stepwise dissociation constants K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11 can be calculated using the following equation:$$[HCO_3^-] = \frac{K_{a1}[H_2CO_3]}{[H^+]}$$where [H₂CO₃] is the concentration of carbonic acid, [H⁺] is the concentration of hydrogen ions, and K_a1 is the first dissociation constant.Substituting the given values into the equation, we get:$$[HCO_3^-] = \frac{(4.3 imes 10^{-7})(0.010)}{[H^+]}$$To find the concentration of hydrogen ions, we can use the following equation:$$[H^+] = \sqrt{\frac{K_{a1}K_{a2}}{[H_2CO_3]}}$$Substituting the given values into the equation, we get:$$[H^+] = \sqrt{\frac{(4.3 imes 10^{-7})(5.6 imes 10^{-11})}{0.010}} = 2.3 imes 10^{-9} mol L^{-1}$$Substituting this value into the first equation, we get:$$[HCO_3^-] = \frac{(4.3 imes 10^{-7})(0.010)}{2.3 imes 10^{-9}} = 6.6 imes 10^{-5} mol L^{-1}$$Therefore, the concentration of bicarbonate ion, HCO₃^-, in a 0.0 10 mol L^-1 H₂CO₃ solution that has the stepwise dissociation constants K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11 is 6.6 × 10^-5 mol L^-1.

Calculate the Concentration of Bicarbonate Ion, HCO3-, in a 0

Calculate the Concentration of Bicarbonate Ion, HCO₃^-, in a 0