Weak Acid/Base Calculations
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Weak Acid/Base Calculations
How do we find the pH/pOH and concentrations of H30+ and OH- of a reaction with a weak acid/base that doesn't completely dissociate?
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Re: Weak Acid/Base Calculations
You would have to make an ICE table and assume that -x amount dissociates and therefore +x amount protonates to form the products. Then you use the relationship between pKa and pKb to determine the concentrations. I watched a pretty helpful video on this: https://www.khanacademy.org/science/che ... quilibrium
Hope this helps!
Hope this helps!
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Re: Weak Acid/Base Calculations
I agree with the above. Weak acids and bases only dissociate partially. If the Ka or Kb is incredibly small, x (amount dissociated) is very very small.
For a Weak acid:
HA <--> H+ + A-
I
C
E
The equilibrium value for H+ can be used to then calculate the pH of the solution. Hope that was helpful.
For a Weak acid:
HA <--> H+ + A-
I
C
E
The equilibrium value for H+ can be used to then calculate the pH of the solution. Hope that was helpful.
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