What he’s trying to explain is he first measures the volume of a standard strong base (e.g. NaOH), and then dump a weighed unknown sample containing some amounts of a weak acid (e.g. citric acid) all into the NaOH. Since the amount is not high and it’s a weak acid, there will be only a little change in pH of the original NaOH. Therefore, the remaining part of NaOH requires another strong acid to reach neutralization. Hence, he titrate the remaining NaOH with a strong acid (e.g. HCl). Once the solution reaches the neutralization point, he can calculate how much HCl was used to neutralize the remaining NaOH. In other word, he can know the no. of mole of HCl used. As the ratio of NaOH to HCl in the reaction is 1 to 1, the no. of mole of NaOH is known as well. Do you remember that he has already measure the volume of the original NaOH before everything starts ? As the molarity of the NaOH is known, the no. of mole of the original NaOH can be calculated simply by multiplying volume with molarity. There is a difference between the no. of mole of the original NaOH and the one of the “remaining” NaOH . Why? Because the difference is the one which has been neutralized by the unknown sample ( which contains a weak acid). Therefore, you can use the difference in no. of mole to find out the no. of mole of the weak acid in the unknown sample. E.g. NaOH to citric acid in the reaction is 1 : 1 . Once you know that, you can calculate the weight of the weak acid. Eventually, you can compare this weight with the one of the whole unknown sample you measured to figure out the weight % of citric acid in the unknown sample. Hopefully it helps.
Thanks you i am an Indian i thought I can't understand this video but I am listen once I understood it very much thank you this video is deeper and no videos are this much deeper
the curve (graph) is wrong but doesn't affect the explanation! on the other hand, well explained! it is helpful to understand the process of back titration
I’m watching this at 1am before my scholarship chemistry exam because things like this have never been well explained and there is virtually no help online for scholarship level stuff.
I thought it gets more acidic because you are adding a weak acid to a strong base, therefore it starts high at a high pH (basic) then gradually lower to a more acidic and lower pH.
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What he’s trying to explain is he first measures the volume of a standard strong base (e.g. NaOH), and then dump a weighed unknown sample containing some amounts of a weak acid (e.g. citric acid) all into the NaOH. Since the amount is not high and it’s a weak acid, there will be only a little change in pH of the original NaOH. Therefore, the remaining part of NaOH requires another strong acid to reach neutralization. Hence, he titrate the remaining NaOH with a strong acid (e.g. HCl). Once the solution reaches the neutralization point, he can calculate how much HCl was used to neutralize the remaining NaOH. In other word, he can know the no. of mole of HCl used. As the ratio of NaOH to HCl in the reaction is 1 to 1, the no. of mole of NaOH is known as well.
Do you remember that he has already measure the volume of the original NaOH before everything starts ? As the molarity of the NaOH is known, the no. of mole of the original NaOH can be calculated simply by multiplying volume with molarity.
There is a difference between the no. of mole of the original NaOH and the one of the “remaining” NaOH .
Why? Because the difference is the one which has been neutralized by the unknown sample ( which contains a weak acid). Therefore, you can use the difference in no. of mole to find out the no. of mole of the weak acid in the unknown sample. E.g. NaOH to citric acid in the reaction is 1 : 1 .
Once you know that, you can calculate the weight of the weak acid. Eventually, you can compare this weight with the one of the whole unknown sample you measured to figure out the weight % of citric acid in the unknown sample.
Hopefully it helps.
Thanks you i am an Indian i thought I can't understand this video but I am listen once I understood it very much thank you this video is deeper and no videos are this much deeper
This video actually makes a lot of sense, compared to other back titration videos on TH-cam. Thank you!
This video needs lots of patience
This comment made me lose patience😕
the curve (graph) is wrong but doesn't affect the explanation! on the other hand, well explained! it is helpful to understand the process of back titration
I am having trouble understanding what your explaining
squad
Do still need an explanation? been two years...
Same
go check out SHAILESH AGNIHOTRI he teachs better than him
@@golmaalhbhai4056 its ok . thanks much graduated from school already
I'd tell you if i messed up the back titration question on my exam after watching this bomb video.
It's been 8 yrs bro
@ it’s been a rough 8 years ngl
I’m watching this at 1am before my scholarship chemistry exam because things like this have never been well explained and there is virtually no help online for scholarship level stuff.
you get that scholarship?
Yes?
this applies to aspirin back titration right?
Yep, still don't understand.
@I killed cupid xD
i know the pain of writing with a mouse..
even me
xD
That buret looks like a wenis.
The audio is like a screeching chalkboard.
Great! This video helps me to understand the main idea of back titration
Thankyou!
What if only a sample of the new base solution was used for the second step? Since the volume of the bases change, wouldn't the moles change?
Can i get a heart...u explain very well
Wow... Very nice lesson
So you have to have at least an idea of the amount of weak acid to know how much excess you have to add?
helpful. give me example of EDTA that can apply in environment
He did not say we titrate weak acid against strong acid in the beginning,didnt he?
this was helpful! thanks
Thank you, that helped a lot.
Thank you. This is helpful :D
Thank you, great video!
Thank you!
Thanks! Great explanation
Thank you! Now I understand it more than when my teacher taught me!
Are you an Australian ?
Thanks!! Very helpful video and explanation
awesome
ขอบคุณครับ ^^ (Thanks!!!)
What?
he flopped to sketch the graph, the solution gets more alkali
I thought it gets more acidic because you are adding a weak acid to a strong base, therefore it starts high at a high pH (basic) then gradually lower to a more acidic and lower pH.
The teaching approach is boring l, the you talk as though you are just from taking a nap, please try to teach with energy and enthusiasm.
Your speech is not clear