Find the Ka Using a Titration Curve
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- Опубликовано: 2 окт 2024
- The pKa of an acid is exactly the same as the pH HALFWAY to the equivalence point!
Then, Ka = 10^-pKa and you're done. Super easy.
Thanks Henderson-Hasselbalch!
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This was uploaded in april..........
he could still have recorded it halloween
I want to believe
Hes saying happy Halloween because most people will be watching this before midterms lol
he knew this material will be on our midterms. midterms after usually after halloween. (fall semester)
"Maybe you did, I don't care."
LOL savage
Just happens to be october 14 when i needed this,Nate is a time traveling chemist.
wow i'm actually watching this on Halloween. how'd he know
Same with me this year.....
well i had a chem lab today on this.
I kid u not, but im also watching this on Halloween
Same lol
lmao its halloween 2018 today and I was so confused when he said happy halloween
Thank you for this video, no more guessing on my lab report :)
"Oh, you want a treat? Well here, let me show you how to find the Ka of an acid from a titration curve!"
Bravo sir, bravo.
Why couldn't my chem teacher just say this... Thank you!
thanks but i think you mean 8.41 and not 8.31?
Jefferson Joosten Yeah, i noticed that too.
I don't care how old this video is I'm commenting because I love you and you just saved my chem grade.
trick-or-treat during april XD
It's two days after halloween...but this was uploaded over two years ago???
i had a very hard time with my lab work but this helps a little. just gotta watch it a couple times. thanks for the video! i hate chemistry with all my heart lol
Just clicked on this and it's Halloween... what a coincidence
Its October 13th 2020 its a tuesday and im stuck in quarantine still so yea
why doesn't everyone make it this easy? thanks!
I was just telling the girls in my class about how easy he made this look because Oowee lol 😂😂😂😂
watching this a day before Halloween, ha ha good timing
You sir, are a blessing
Thank you so much!! Truly simplified the concept and I greatly appreciate it.
Does this work only for Weak Acids and Strong Bases of the same concentration? Or does it work for any concentration? Also, I don't understand why the strong base concentration stays at 10. Doesn't the added amount of the strong base get neutralized immediately by the weak acid? Really confused Chem student here >.
+Michael Jonathan Good question.
This video is great, it helps me a lot. thank you
Wholesome intro.
Weird how i am watching this 4 days from halloween...............
cool, how do you work out the mass of the acid using all of these things???
how exactly do you know where the equivalence point is on the graph?
the equivalence point is the point on the curve with the steepest incline, but this can be hard to see with the naked eye. You just have to make an estimate, unless you use an auto-titrator, which gives you the equivalence points.
i don't know if i can explain this by writing but i will try . You see there are two turning points in the graph right? ( For instance, At 0:54 chemistNate is pointing one of that point which i meant with his pinky!=D . So you draw the tangent through this line.At 0:19 he is pointing the another point , here also u draw the tangent line parallel to the other line)). Now they should be very parallel and now measure the distance between them and divide by 2 to get the midpoint and u get somewhere around the same point like he is mentioning as equivalence point in this video and draw a line from that point to y-axis parallel to x-axis to get the ph at this equivalence point. this is how you figure out equivalence pt. and ph just by looking at titration curve. I hope i didn't exaggerate.
wow i'm actually watching this on Halloween. how'd he know
literally copied tc lol
Well presented, thank you. Can you do something diprotic?
Why do we need to use the equation if we can just find Ka from pKa. No need for the log(base/acid) right?
Heard the intro then checked the date of the video. It's currently Oct.15th so that was quite the surprise lol. Regardless, thank you for the great explanation!
I don't understand the difference between the equivalence point and the 1/2 up the buffer area. At the equivalence point the amount of acid and base are equal but at the buffer point the concentrations are equal. I'm having a hard time understanding the difference. I thought that if the concentrations were equal then that would be equivalence. Can someone help?
+samxyx It's a little hairy but the distinction is as follows. At the equivalence point, the amount of strong base and weak acid are equal. At the midpoint of the titration, the concentration of the acid and the conjugate base are the same. I hope this helps! Disclaimer: I am no expert. But this is my understanding
I am confused as to how two substances could have the same concentration in a liquid but exist in different amounts at the same time. Such as at the midpoint of the titration. Could you explain this?
Hope I am not being too much of an idiot.
+samxyx Not at all! Okay, at the midpoint of the titration, the concentration of weak acid and its conjugate base are equal. And they exist in the same amounts as well. We would represent this as [HA] = [A-]. This is occurring at the midpoint.
Okay, at the equivalence point, the moles of weak acid is equal to the moles of strong base added. We might represent this as [HA] = [OH-] or even more simply [H+] = [OH-]. Again, these are at the same concentration and the same amount. Now, the confusion might arise since this is a weak acid. Even after the strong base has neutralized all of the H+ formed by the weak acid, the conjugate base of the weak acid will react with water to form a little bit of excess [OH-]. This is why the pH of the equivalence point is not exactly 7. If you want a more detailed explanation, I'm happy to give it! Weak acid-strong base titrations are one of the harder concepts in AP Chem or intro chem to grasp.
Half Point: concentration of acid = concentration of base
Equivalence point: no. of moles of acid= no. of moles of base
How could two different substance could have the same concentration but exist in different amounts at the same time?
Neutralisation basically is the reaction between acid and base to form water (forget the salt once) i.e they must have ph = 7 (for strong acid and strong base, lets say)
Well lets say the concentration of acid = 1 M
concentration of base = 10 M
you have 25 ml of acid (1 M ) in your flask, right.See the concentration of that base is too high , you dont need much of this base to neutralise that acid with small concentration and which implies they both have same concentration at midpoint but the amount (VOLUME) of acids and bases are different, see?
Is this universal, for all types of acids, or does this change between weak acids and strong acids?
Thanks for the help. Happy Halloween.
u saved my life sir
Watching this during Halloween 2018
Thank you, cleared up so much confusion.
Thank you for posting this!
THANK YOU SO MUCH! SO GOOD!
thank u so much dude!!!!!!!!!!! love ur videos
... I'm watching this on Halloween. WHAT THE ACTUAL FUCK?????????? Is this guy a wizard or something... ILLUMINATI CONFIRMED!!!!!!!!!!!!!!
I still dont understand how he got pKa
lol so gansta tho at the end
Thanks for making this short and simple!
I understand how to find Ka and all, but how do I find the equivalence point without Ka? Do I add the two points at the beginning and end of the jump to find the equivalence point?
***** The equivalence point is always where the curve is steepest (the point of inflection).
I thought at the equivalence point [base]=[acid]. why is it half of the equivalence point?
bless you. thank you. this was so concisely and clearly explained
you've got a great personality. thanks for the video!
how to find the pH of the second equivalent point?
Excellent explanation!
Very useful! My quant. book gave in-depth examples on how to calculate pKa from Gran plots but neglected the original titration curves!
you starting the video with happy Halloween scared me. you posted this in april how did you know that 10 years later i would be watching this on Halloween youre freakin me out man
Needed this video for a lab today. Got a shock when you wished me Halloween from 10 years ago and it is currently Oct 31st lol
You sound so rebellious, this video is funny and educational at the same time.
This is the best thing since sliced bread
sliced bread was never this good.
To specify, at the half equivalence point the concentrations of the CONJUGATE base and the Acid are equal I believe. At the equivalence point, concentrations of acid and BASE are equal. Correct me if I'm wrong
its 2 am you just saved my life on an assignment thank you
Lmao also here because I saw this was posted in April but I'm here for a lab due 10/29 and he said happy Halloween! Haha Spooky!
Your good chemist nate !!
that was way too fast... thanks though, and i'm sure it's all correct and everything, but some of us are here because we are slow......
can you help me to specify what is the different between ph at the point of maximun buffering and equivalence point?
Love this guy 😂💯
THANK LORD THIS VIDEO EXISTS... EXPLAINS ALL MY QUESTIONS... THANK YOU SOOOO MUCH
Confusing.... no one seems to have an insight into where students get lost with this material
How the hell did you know it was halloween
Why does he sound like Dr. Evil from Austin Powers?
Happy Halloween to you too sir
Excellent 🔥
I don’t know, I don’t care
*Cue the "We're not worthy scene from Wayne's World!*
This just made my life s much easier!
Happy Halloween mate.
certified banger!
My cat loves this video
you are the goat.
Thanks to this video I got my pre-lab done much faster.
Thank you so much for making the video. I wish my teacher would actually teach.
half of 16.82 is 8.41.
0:32 Correct me if I'm wrong. It shouldn't be "we have added just as much base as we have of acid" because molarities could be different. Proper wording would be something like added the correct amount of moles of base to completely neutralize the acid, which is usually like a 1:1 molar ratio.
This is correct, and it crossed my mind as I made the video. But I decided that I liked it as is.
Really strange how im watching this a day after halloween
Is the "base" the reactant or the salt in the product?
thank you so much
Is there a way to somehow calculate the pH of the half nuetralization point if you have the initial pH of the acid and equivalence point?
You're a lifesaver! thank you soo much
Best treat ever.
u nice guy. tyty
the human who made this video is a nerd and I am forever in their debt. long live the nerds
Madeline Murray So what?
Thank you so much for this video! It helped me so much! :D
you are amazing
thanks
thank you thank you!!!!
A boat
ChemistNate, you are a godsend! Thank you so much!
Bless anyone else have AP chem tomorrow
IT'S LITERALLY OCTOBER 31 WTF
THIS WAS SO HELPFUL FOR MY LAB REPORT THANK YOU
thank you so much!! helped me out on an entire lab!
great video! helped me alot! Thanks!
Thank you for this video, it's really helpful!
That was really good. Thank you.
wow so helpful thanks
🔥🔥🔥
very nice sir!!! Thank you!