Ka and Kb values
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Ka and Kb values
Will we always be given the Ka and Kb values if they are needed to solve something else in a problem? Some of the textbook problems don't always give them so I'm wondering if we need to memorize some of them?
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Re: Ka and Kb values
Of course I'm not 100% sure but I highly doubt we need to memorize any Ka or Kb values. It makes sense that we need to know common strong/weak acids/bases so we can set up equations and have an idea of how the problem will play out. But knowing certain Ka or Kb values seems like information that should be given.
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Re: Ka and Kb values
Im pretty sure we will always be given Ka/Kb values if they are necessary to the problem. The textbook doesn't always give them because they want us to refer to the Ka value table given prior in the reading. Additionally, if an acid or base is known to be strong then the Ka/Kb value is not necessary because we can assume 100% depronation.
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Re: Ka and Kb values
I believe that we will either be given the values of Ka and Kb or we will be given the necessary variables to solve for Ka and Kb using these equations:
Ka x Kb = Kw = 10^-14
Ka or Kb = [products]/[reactants]
Ka x Kb = Kw = 10^-14
Ka or Kb = [products]/[reactants]
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Re: Ka and Kb values
A lot of the time Ka and Kb values are omitted is because we might be dealing with strong acids/bases where we can assume 100% disassociation. Calculating problems of weak acids/bases without the necessary Ka/Kb values is often not possible without specific information required.
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Re: Ka and Kb values
I would assume that we will be given the necessary information needed in order to correctly solve the problem, I am not too sure on the specifics though. For example, some of the textbook charts provide the Ka value of the bases’ s conjugate acid and expect you to know how to solve for Kb and use that to determine other necessary information. You would simply do this through plugging in the given values to the equation Kw=Ka*Kb.
Re: Ka and Kb values
Im pretty sure they will be given or if not they will given enough information to calculate the Ka or Kb values ourselves using pKa or pKb
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