Ka and pKa
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Re: Ka and pKa
Im not sure if this is what you mean by their relationship but hopefully this helps!
Ka = -log Ka
Ka = 10^-pKa
- the smaller the ka and the larger the pka, the weaker the acid
Ka = -log Ka
Ka = 10^-pKa
- the smaller the ka and the larger the pka, the weaker the acid
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Re: Ka and pKa
Ka is the dissociation constant of the acid (higher the Ka the stronger the acid because the more it dissociates), and pKa is the negative log of that.
So pKa = -log[Ka] and Ka = 10^-pKa
So pKa = -log[Ka] and Ka = 10^-pKa
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Re: Ka and pKa
Ka can also be used to calculate Kb since [Ka]*[Kb]=10^-14
PKa can be used to calculate PKb since [PKa]+[PKb]=14
PKa can be used to calculate PKb since [PKa]+[PKb]=14
Re: Ka and pKa
The Ka value is directly proportional to the acidity of a molecule while the pKa is the pH value at which a chemical species will accept or donate a proton. The relationship between Ka and pKa are described by the Henderson-Hasselbalch equation. Hope that helps!
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Re: Ka and pKa
Ka is indicative of the acidity of a molecule, so a higher Ka value indicates a stronger acid. pKa is the negative log of the Ka value.
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Re: Ka and pKa
Hi!
pKA = -log (Ka) & Ka = 10 ^ -pKa
Ka is the acidity constant that is used to determine equilibrium constants for acidic reactions. pKa determines the strength of the acid. The lower the pKa, the stronger the acid.
I hope this helps!
pKA = -log (Ka) & Ka = 10 ^ -pKa
Ka is the acidity constant that is used to determine equilibrium constants for acidic reactions. pKa determines the strength of the acid. The lower the pKa, the stronger the acid.
I hope this helps!
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Re: Ka and pKa
Ka is the equilibrium constant for a weak acid, pKa is just the -log(Ka). A lower pKa means a stronger acid, it uses the same scale as pH.
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Re: Ka and pKa
pKa is the negative log of Ka, -log(Ka). The larger the Ka, therefore the smaller the pKa, the stronger the acid will be.
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Re: Ka and pKa
Hi! pKa = -logKa, while Ka=10^-pKa. pKa determines the strength of the acid, a low pKa indicates a stronger acid.
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Re: Ka and pKa
The "p" in pKa is indicative of -log
Therefore, pKa is -log(Ka), which means that Ka is 10^-pKa
Therefore, pKa is -log(Ka), which means that Ka is 10^-pKa
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Re: Ka and pKa
In mathematical terms, pKa = -log(Ka). Therefore, it can also be noted that Ka=10^-pKa.
Ka is the dissociation constant of acid, basically used to indicate how strong an acid is. The higher than Ka is, the stronger the acid is. pKa is just simply the negative log of Ka. This allows for a more simpler expression of how strong or weak an acid is (since the numbers are "cleaner").
Therefore, since pKa is the negative log of Ka, this time, the lower the pKa is, the stronger the acid is.
Ka is the dissociation constant of acid, basically used to indicate how strong an acid is. The higher than Ka is, the stronger the acid is. pKa is just simply the negative log of Ka. This allows for a more simpler expression of how strong or weak an acid is (since the numbers are "cleaner").
Therefore, since pKa is the negative log of Ka, this time, the lower the pKa is, the stronger the acid is.
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Re: Ka and pKa
As other posts already stated, pKa = -log Ka and Ka is 10^-pKa. The larger the pKa is, the weaker the acid.
Re: Ka and pKa
The relationship between pKa and Ka can be shown through: pKa= - logKa. They both relate to the strength of an acid.
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Re: Ka and pKa
As Dr. Lavelle has mentioned, the lowercase p just means "take the -log base ten". So in order to go from Ka to pKa, you must take the -log base 10 of Ka. In order to go the opposite way, you must do 10^pKa to get Ka.
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Re: Ka and pKa
The value of Ka can be expressed as pKa, much as pH. pKa is equal to -log Ka. The weaker the acid, the higher the pKa. For each conjugate acid and its conjugate base pair, pKa is a constant.
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Re: Ka and pKa
pKa = -log(Ka)
Ka = 10^-(pKa)
The larger the pKa, the weaker the acid.
The smaller the pKa, the stronger the acid.
Ka = 10^-(pKa)
The larger the pKa, the weaker the acid.
The smaller the pKa, the stronger the acid.
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Re: Ka and pKa
p means to take the -log of something. So, the relationship between Ka and pKa is that pKa = -logKa
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Re: Ka and pKa
-log(Ka) = pKa
If you're having trouble remembering this, I think its easiest to always refer to the pH and [H+] relationship:
-log[H+] = pH
As you can see these equations are very similar (p_ is the negative log of _) and I think if you memorize just one, you'll be able to always derive the other!
If you're having trouble remembering this, I think its easiest to always refer to the pH and [H+] relationship:
-log[H+] = pH
As you can see these equations are very similar (p_ is the negative log of _) and I think if you memorize just one, you'll be able to always derive the other!
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Re: Ka and pKa
another relationship is that Ka is directly related to pH, but inversely related to pKa.
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Re: Ka and pKa
Ka refers to the equilibrium constant associated with the dissociation of an acid which is usually expressed in some sort of scientific notation since it is often times very small for weak acids. Thus, we can take the -log of this value to get the pka value which allows us to gage the relative strength of the acid.
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Re: Ka and pKa
The acid dissociation constant, Ka, is used to determine strong acids from weak acids. Strong acids have high Ka values (they dissociate a lot and so therefore they have a larger concentration of products). Weak acids have low Ka values (they do not dissociate a lot and so they have a greater concentration of reactants). The Ka value is found by looking at the equilibrium constant for the dissociation of the acid. The higher the Ka, the more the acid dissociates. pKa is the negative log base ten of the Ka value (acid dissociation constant). It measures the strength of an acid — how tightly a proton is held by a Bronsted acid. The lower the value of pKa, the stronger the acid and the greater its ability to donate its protons (the weaker the proton is held). Larger the Ka, smaller the pKa, the stronger the weak acid. Smaller the Ka, larger the pKa, the weaker the weak acid.
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Re: Ka and pKa
Hi, Ka is the ionization constant of an acid, and pKa=-log(Ka). Because of this log scale, a large Ka value will have a small Ka value, both of which indicate a stronger acid.
Re: Ka and pKa
Hi, pKa=-log(Ka) the relationship between Ka and pKa is similar to that between pH and H3O+. The more acidic the acid is, the larger the Ka is and smaller pKa is.
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Re: Ka and pKa
Ka is the acid dissociation constant and is used to represent the strength of the acid. pKa is the negative log of Ka. The large the Ka value, the smaller the pKa and the stronger the acid.
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Re: Ka and pKa
Ka is the acid dissociation constant and is used to represent the strength of the acid. pKa is the negative log of Ka. The large the Ka value, the smaller the pKa and the stronger the acid.
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Re: Ka and pKa
Ka refers to the equilibrium constant of the acid. pKa refers to the pH of Ka. Their relationship is as follows: pKa = -log(Ka).
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Re: Ka and pKa
The relationship between Ka and pKA is the smaller the value of Ka, the larger value of pKa. To convert from one to the other, ka = 10^-pKa and pKA = -logKa.
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Re: Ka and pKa
The relationship between Ka and pKa is given by the following formulas:
Ka = 10^(-pKa)
pKa = -log[Ka]
Ka = 10^(-pKa)
pKa = -log[Ka]
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Re: Ka and pKa
Ka is the acidic disassociation constant that is the equilibrium constant of the disassociation of an acid and is known as Ka. The strength of Ka is determined the same way we determine K: [products]/[reactants]. The larger the Ka, the more the acid dissociates and if the value is high enough, it can be determined as a strong acid which means it completely dissociates into its ions. pKa is a number that is similar to pH in which it determines how weak or strong the acid is. When comparing the two, pKa=-logKa. Similarly, Ka can be determined by pKa since Ka=10^(-pKa).
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Re: Ka and pKa
pKa is the -log of the Ka, using the base 10. Let me know if you have any more questions
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Re: Ka and pKa
pKa is finding the -log of Ka. Another way can is Ka is finding the -10 to the value of pKa as the power (-10^pKa).
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Re: Ka and pKa
ka is the acid constant and pKa is the -log of that. what p usually stands for in these scenarios is by taking the negative log of any amount you can place the values on a much easier to read and understand scale that gives you the relative strength of any acid or base.
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Re: Ka and pKa
pKa is the negative log of Ka similar to how Ph is the negative log of H+ concentration
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Re: Ka and pKa
equation wise this is the relationship, pKa = -log[Ka] and Ka = 10^-pKa. The larger the Ka value, the smaller the pKa value and stronger than the acid is. The relationship is similar to the relationship between pH and H+
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Re: Ka and pKa
Ka is the equilibrium constant for the dissociation of a weak acid and measures the concentration of products/reactants. The greater the value of Ka, the greater the dissociation of the acid. pKa is equal to -log[Ka] and is essentially just another way of measuring the acid dissociation that is comparable with pH. This means that the higher the pKa, the lower the Ka and vice versa.
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Re: Ka and pKa
The relationship between Ka and pKa can be found through this formula :pKa = -log Ka. Hope that helps :)
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Re: Ka and pKa
the p just means that you take the -log() of anything, pH means -log(H+) , pKa means -log(Ka)! easy as that
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Re: Ka and pKa
Like with pH, pKa just means taking the negative log of the Ka to get value between 0-14.
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Re: Ka and pKa
Like with pH, pKa just means taking the negative log of the Ka to get value between 0-14.
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Re: Ka and pKa
The relationship between the two is that Ka represents the acid constant and in order to obtain pKa you would take the -log() of Ka.
The relationship would be
"The larger the pKa, the weaker the acid. pKa is a constant for each conjugate acid and its conjugate base pair".
The relationship would be
"The larger the pKa, the weaker the acid. pKa is a constant for each conjugate acid and its conjugate base pair".
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