Buffers and Hendersen-Hasselbalch

Buffers and the Hendersen-Hasselbalch equation

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Education

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• Buffers
• and
• the
• Hendersen-Hasselbalch
• equation

[BF1]

@rinwhr He makes a comment in a previous video that he makes some wrong assumptions in the last 3-4 min. So he made this video that just cut the last few minutes off.

[namanphoto]

thanks for the conceptual idea of hendersen hasselbalch but can you teach us ICE tables???

[jsmcrawler]

I have done HH a dozen times never even though it was derrived from the original equation

tks

[RISEofTIBET]

as always thank you kindly for your great instructions. i was wondering, are you left handed? thanx

[FarrahGreye]

ur awesome!!!!!!!!!

[UnclePorkflaps]

@savvy22dew Nearest I can tell, you have mistake the "p" in this equation as a regular variable. It is actually the short hand for -log(). Thus p(Ka) = -log(Ka) and p(HA/A) = - log(HA/A). Log functions have a few unique properties, one of which is that log(X*Y) = Log(X) + Log(Y), which explains why

p(K * [HA]/[A-]) = pK - log [HA]/[A].

Sal has a proof of this concept on his website in the algebra section if you are interested in why this is so. Hoped that helped!

[hahs4]

I love you Sal

[savvy22dew]

Did you distribute wrong?

for calculating the hendersen-hasselbalch eq.-

p(K * [HA]/[A-]) = pK k * [HA]/[A-] NOT pK - log [HA]/[A]

you can only distribute if the things inside parenthesis are added or subtracted:

6(3+2) = 6*3 + 6*2 = 18 + 12 = 30 and 6(3+2) = 6 * 5 = 30 so it checks out

you did 6(3*2) = 6*3 + 6*2 = 30 but 6*6 = 36. Not Equal!!

so i am confused. i think i explained why well enough, would someone clarify for me?

[Transpacity]

@norwayte He cut off the end since he said that volume doesn't matter.

[rinwhr]

Did it get cut off at the end...?