Ph and PKA
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Claire_Kim_2F
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Ph and PKA
I was wondering if the pka is higher than the ph then does that mean it is neutral according to the lecture #28 where Dr.Lavelle said it is negative because the pka is lower than the ph? Also what exactly does pka mean because I thought it was strength of acid but Dr.Lavelle said if it is more acidic is has a lower pka?
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Claire_Latendresse_1E
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Re: Ph and PKA
Nice name! The reason that an acid is more acidic when it has a lower pKa is that pKa = -log[Ka]. An inverse relationship would form (as Ka increases, pKa decreases).
When pH < pKa (acidic conditions), the acid gets protonated as HA. It will be neutral.
When pH > pKa, the acid will give off a proton (the acid is stronger than the solution). It will have a negative charge after it gives off its proton and becomes A-.
When pH < pKa (acidic conditions), the acid gets protonated as HA. It will be neutral.
When pH > pKa, the acid will give off a proton (the acid is stronger than the solution). It will have a negative charge after it gives off its proton and becomes A-.
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Ivy Tan 1E
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Re: Ph and PKA
Hi!
Adding on to the response above, when pH < pKa, the solution is already in an acidic environment because the pH is lower, so the acid will not dissociate to make the solution even more acidic (it is neutral). When pH > pKa, the solution is in a basic environment because the pH is higher, so the acid will dissociate and become ionized. Hope this was helpful!!
Adding on to the response above, when pH < pKa, the solution is already in an acidic environment because the pH is lower, so the acid will not dissociate to make the solution even more acidic (it is neutral). When pH > pKa, the solution is in a basic environment because the pH is higher, so the acid will dissociate and become ionized. Hope this was helpful!!
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Claire_Kim_2F
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Kaili Valenzuela 2B
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Re: Ph and PKA
Claire_Kim_2F wrote:Is ha the base and a- the acid component of the equation?
Actually, HA is the acid and A- is the base
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Inderpal Singh 2L
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Sofia Lombardo 2C
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Re: Ph and PKA
Claire_Latendresse_3J wrote:Nice name! The reason that an acid is more acidic when it has a lower pKa is that pKa = -log[Ka]. An inverse relationship would form (as Ka increases, pKa decreases).
When pH < pKa (acidic conditions), the acid gets protonated as HA. It will be neutral.
When pH > pKa, the acid will give off a proton (the acid is stronger than the solution). It will have a negative charge after it gives off its proton and becomes A-.
Sorry, I am just a bit confused about the charges. Like if we were comparing pOH and pKb if the pOH > pKb, would the base get a positive charge?
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