The Ka of a monoprotic weak acid is 0.00279. What is the percent ionization of a 0.159 M solution of this acid?
I got 12% to this question, but it's wrong? How do I solve this?
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I would start by writing out the equation for monoprotic weak acids and water (HA + H2O (l) <--> H + A). Then set up your ice table with HA, H, and A, solving for x using Ka = [H][A]/[HA]. From there, you can determine percent ionization using the equation [H_equilibrium]/[HA_initial] x 100%.
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Re: Achieve #2
In order to solve this problem, you must use the quadratic formula to get the value of x for the concentration of the conjugate base since the ka is greater than 10^-3. After solving for the two possible values of x, you must choose the correct one. The percent ionization is then the value of x divided by the initial value times 100.
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Re: Achieve #2
Use an ICE box to determine your final quantities. You will have to use the quadratic formula because Ka is too big to assume it is negligible. After finding all the final concentrations take the H+ concentration and divide it by the initial monoprotic acid concentration. When multiplied by 100% this will yield the percent ionization.
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Re: Achieve #2
Hi!
Remember that when you do the quadratic formula to pick the positive value. This will save you some time because you don’t have to deal with the negative value.
Hope this helps :)
Remember that when you do the quadratic formula to pick the positive value. This will save you some time because you don’t have to deal with the negative value.
Hope this helps :)
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