What is pKa and Ka exactly?
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Re: What is pKa and Ka exactly?
pKa is used to describe acids. Lower pKa= stronger.
Ka is the acid dissociation constant. -logKa=pKa
Ka is the acid dissociation constant. -logKa=pKa
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Re: What is pKa and Ka exactly?
Ka is the equilibrium constant of an acid. If Ka is less than 1, then the acid is considered very weak. pKa is the negative log of Ka, which is just used to make the math a bit easier. The smaller the pKa, the stronger the acid.
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Re: What is pKa and Ka exactly?
I think Ka is the dissociation constant and pKa is the negative log of Ka.
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Re: What is pKa and Ka exactly?
pKa is basically a simplified way to view Ka (-logKa), just as pH is a simpler scale to interpret concentrations of H30+.
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Re: What is pKa and Ka exactly?
Ka is [product]/[reactant] in an acidic reaction. pKa is simply the neg log of Ka.
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Re: What is pKa and Ka exactly?
Ka is acid dissociation constant and represents the strength of the acid. pKa is the -log of Ka, having a smaller comparable values for analysis. They have an inverse relationship. Larger the Ka, smaller the pKa and stronger the acid.
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Re: What is pKa and Ka exactly?
Yes, it would. The weaker the base, the smaller the value of Kb and the greater the value of pKb. Essentially, a large Kb value indicates the high level of dissociation of a strong base. A lower pKb value indicates a stronger base.
Re: What is pKa and Ka exactly?
The acid dissociation constant, Ka, is a quantitative indicator of the strength of an acid in a solution. pKa is simply the negative log of ka.
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Re: What is pKa and Ka exactly?
The pKa is just the pH level. It helps you see the H+ concentration more easily. Just like how you would calculate the pH = -log[H+] or -log[H3O+], pka is found using a very similar formula; pKa = -log[Ka].
Ka is your acid dissociation constant which just shows how much dissociation that particular acid will undergo in the product side or the reaction side. That is found using this formula: Ka=[A-][H3O+]/[HA]
or a more simplified way to show this formula: Ka=[products]/[reactant]
The larger the Ka the stronger the acid, generally if it's above 1 it's a stronger acid, less than 1 it's a weaker acid. The larger the Ka value the smaller the pKa value so it is an inverse relationship.
Ka is your acid dissociation constant which just shows how much dissociation that particular acid will undergo in the product side or the reaction side. That is found using this formula: Ka=[A-][H3O+]/[HA]
or a more simplified way to show this formula: Ka=[products]/[reactant]
The larger the Ka the stronger the acid, generally if it's above 1 it's a stronger acid, less than 1 it's a weaker acid. The larger the Ka value the smaller the pKa value so it is an inverse relationship.
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Re: What is pKa and Ka exactly?
Ka is the acid dissociation constant, and is usually expressed as [products] / [reactants]. If Ka is high, the acid in question dissociates easily, which means we are dealing with a string acid. Because p(anything) = -log(anything), we know that the inverse relationship holds for pKa (lower pKa corresponds to stronger acid).
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Re: What is pKa and Ka exactly?
Ka is how acidic or basic something is, and pKa is the negative log of Ka
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Re: What is pKa and Ka exactly?
Ka is the acid dissociation constant, which is an equilibrium constant meant to describe the dissociation reaction of an acid in solution. A higher Ka value indicates a stronger acid. pKa is the -log of Ka, which returns a more manageable number.
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Re: What is pKa and Ka exactly?
Just as an additional note, I think Dr. Lavelle mentioned in 14A that whenever there's a "p" in front of something, it means to take the negative logarithm (for example pH is the negative log of hydrogen concentration).
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