Buffers

[GamingLabel]

This video is good for the basics :)

[minerman6767]

@imalazykid the OH- is a strong base meaning it is far more likely to react with that instead of the A-

[DocterApricot]

shouldn't there be a salt here somewhere? Because what I know is that an acidic buffer is actually a mixture of a weak acid with a solution of its salt of a strong base

For example:

CH3COOH(aq) with NaCH3COO

and a basic buffer is made by mixing a solution of a weak base with its salt of a strong acid.

For example:

NH3 with NH4Cl

[imalazykid]

@7:30, sal mentions that the proton from HCl would react with OH- and neutralizes the reaction. And then, the reaction shifts to the right to make up for lost Hydroxide (OH-) ions. I get that. But isn't there a chance that same proton can also react with the A- too instead of OH-? And lets say, it did react with the A-, then according to Le chatelier's principle, wouldn't the reaction shift to the right, creating more OH- and thus increasing the pH?

[googoo120]

how come i didnt know about this sooner?

[lalax0lauren]

this is helping me pass chemistry. THANK YOU!!!

[jimmibooyah]

i cant thank you enough! literally saved my academic life.

[crucio6199]

This video was absolutely amazing. Understood more in 18 minutes then in 3 hours of my professor's class.

[dhart2]

@abcdeffedcba2 true, but experimentally base would be added to acids by procedure..you know, titration..

[thepokigur]

Are you single?!?

[Bugz904]

OK as useful as that was for understanding, some of the words used wouldn't be awarded marks , especially with my exam board. They want you to say a buffer is a solution that minimizes or resists changes in pH. The mark scheme says you need a series of equations which you demonstrated well. And also to say what happens when you add an acid ( [H+] increases reacts with negatively charged base from acid dissociation. Etc. After doing a few questions its more clear what they are after.

[TheNilan92]

Déjà vu ! o.O :D

[FarrahGreye]

ur awesome



[backhandable]

3 teachers lost there jobs in the making of this video.

[ewenson111]

doesn't the H+ and a- dissapear when you add NaOH because Na reacts with the acids conjugate base to form a salt as well as the OH taking the H+ to form water. Here you are saying that only the OH takes the H+

[qrais]

This is so wrong, oh my god..base DOES NOT react with the hydronium, it reacts with the weak acid prodicing corrosponding base and water...acid reacts with the corrosponding base

[Zzz230210]

thanks a lot u explain it very well (Y)

[LyGraceDG]

THANK YOU!

[atatatr]

thank a u so much!!!!!!

[purplepick1]

Thank you for explaining to me WHYYYYYY!!!!!!!!!

ahhhhhhhhh SO FRICKEN HAPPY!!!! HHAHAHAHHA

[Caradepato2]

KHAAAAAN!

gread videos. Very usefull, and they are a big help in my studying for my may IB exams..

[rajatdixit007]

Khan-jugates !

[lisapizza174]

You are amazing.

[Bythesw23]

I dont know about the American System of Chemistry lessons. But in Europe we use the formula H30+ + OH- ---> 2H20 (l) Cause If you count OH- as molecule you need to count H30+ as molecule aswell. The oxonium ion.

Also the volumes does count, but you already told in your video. At our classes we usually have it so that the volume change does not really affect the buffer capacity.

[AbhiLabi]

@Bythesw23 Hey Im from canada and yes we follow that volume rule, same as you guys, however the H3O+ is also used but its called Hydronium because its with the water, oxonium is in general for all molecules with that formula

[SRakash]

what do u guys knwo about pH=pKz+-1 ?? 

[Hadoyful]

Thank you very much

you really saved my life ..

[jlin9268]

there no such thing as a ph 0 btw

[truballergirl]

@jlin9268 actually there is. The pH of 1.0 M HCl is 0

[truballergirl]

@jlin9268 actually there is. The pH of 1.0 M HCl is 0

[100percentgreek]

why cant all chemistry teacher teach like this?

[bincemayo23]

haha I swear i was thinking earlier in the video that pH would change by adding more water

[pshinghal]

17:21 pH goes UP not DOWN

[mingalabaa]

You are an excellent Chemistry teacher. I have Chemistry degrees (BS, MS). It's been a long time I did any Chemistry. Now, trying to get back in the fields, I am taking a grad class (Separation Methods) and needed to reviewing the material on buffer, your explanation at 17:10min is just unbleivable in understanding the relationship between pKa and PH , just as I needed to hear.

[theK0OKS]

your colours are so random hahahaha

[mobius946]

Is possible that your video-conferences are subtitled into Spanish or other? Thanks if yes. We khow you do not have time for it.

[missesceo10]

this is VERY HELPFUL! please keep the videos coming! I can't wait to check out the rest of them..

[nbableful]

How can I calculate the pH range of the buffer? from certain point to certain point , the buffer resisting the pH range, how can I know that by calculation? is it experimentally or I can do it from the calculation?

Thank you very much

[muslikid]

But surely a weak acid or a weak base on its own cannot act as a buffer solution? because isnt a buffer solution made out of a weak acid and the salt of that weak acid? whats the point of the salt then if the weak acid can dissociate into its conjugate on its own?

Thanks!!!!

[jhille85]

Sal should replace the Hulu Announcer Guy if he ever retires lol.

[awaizy]

Awesome. Your explanation at the end was done well, too. I was wondering about that in class today and you cleared my doubts.

[24NerF]

How can you tell whether two substances worm an acidic buffer or a basic buffer??

Pls help... Also for the HH equation, where do we obtain the concentrations of acid and base from?

[QNeville]

5 stars are getting played out so I feel like coming over there and high fiveing you.

THANK YOU!

[stretchyrubberbands]

"I would've thought intuitively thought if I add a lot more volume to this and I have the same amount of hydrogen atoms then pH is going to go down."

Won't pH go up if it gets more diluted? Cuz [H] goes down, and pH = -log[H]?

[hamidnia101]

makes sense to me

[ashababe56]

@stretchyrubberbands It won't go down because water will dissociate to form H+.. and it won't go up because it's also forming OH-... I think...

[stretchyrubberbands]

@ashababe56 What I meant was that pH goes UP as [H+] goes down, which was the opposite of what Sal said.

[denzelnolet]

It's worthy to note that for the buffer to actual "work," you need significant amounts of the weak acid/base and its conjugate. So if you're adding a large amount of HCl to a buffer with small amounts of the buffering components (ie a weak base/acid with it's conj salt), the pH will change significantly.

[Qasimbajwaa]

amazing. simply amazing. i get it. amazinggggg.

[nanotech71]

Buffer,,- the Chemical "bumper" or shall we call it the "shock Absorber"

[bobisfreaky]

umm i am kind of confused

in log laws log (xy) = log x + y ? is that true

because in this video

log (xy) = log x - log y

but anyways great lectures they are very well done

and help alot

[gnosiophobe]

i don't really remember any of the log laws, but there's a negative sign in front of the log (xy).

so if

log (xy) = log x + log y

then

-log (xy) = log x - log y

[hamidnia101]

go to 13:04

-log(xy) = - log(x) - log(y)

[oridniv]

you have a sexy voice...it's nice to have it in memory when not stalling on my finals..thanx so much

[jf1gd2]

@oridniv h0m0 alert

[bhrzali]

Sal the god!

[Abhii0]

"Straight up water" awesome :)

[Cherivier]

you're an awesome teacher sal!

[macooper1234]

I thought the principle was well noted. Sometimes it is intuitive to think that more will be more, all in all; but, this case is a little different--more Hydrogen space does not necessarily mean more acidity, because it is not the vacuum, or void, that enhances the pH but the H it self; so, on that note, it breeds an understanding that more H means more acidity.

Nice videos. I've seen a lot. Let me know if I can help, here, in Vermont.

-Mike

[LordAlda]

First glance, it sounded like you were disagreeing with the video. After watching it, I understood that you were just answering his question. :-P

[speckhard2]

@macooper1234 that's a good explanation

[macooper1234]

@speckhard2 They have a SixtySymbols on here: it's a video thing like this but particularly about chemistry--I think they have a physics section at that school, in England (which produces the videos). They are quite interesting!

[CodyClair]

Thank you for the videos on chemistry.

Iam a college chem. major and so far these are well below my current range.

But I hope they, inspire the younger generations to study this amazing subject.

Cody Auclair

[LordAlda]

I'm in college chem, and so far these videos are helpful in reviewing before my lectures.

[Troinik]

thx

[SuPahGoOinc]

I love learning from your channel.