In this video is shown how to perform a fehling's test and how to prepare fehling's solution. As an example different sugars are tested. Patreon: / randomexperimentsinter...
If you want to remind yourself of this easily, think of that among us task where you test 4 or 5 test tubes and they are all blue, when you check back on it one of them turns brick red, I never knew that was added in that game until when I first learnt about this
Im doing this at the science month on 23 of november Its proving glucose in honey and i need to explain everything that happeneds and why..the expiriment is a bit short so i wanted to see a video explanation so that i know more things that i can say there.Didnt see more than i knew but thanks!
Excuse me, can I ask you why the sucrose + citronensäure(citric acid anhydrous) mixture shows the color change? I want to know the principles behind that.
If you can explain for me, I'd be very happy. fullofsoulman@gmail.com this is my e-mail address. You can send me an e-mail for additional explanation. Have a nice day ! :)
It's been four years, but I'm writing so that someone else doesn't have to google. Basically, sucrose doesn't give the Fehling's test because the aldehyde group (-CHO) is locked up inside the ring due to the glycosidic bond formed. But this glycosidic bond can be broken up in acidic environments, so when the citric acid is added along with the sucrose, it breaks down into glucose and fructose, which are the constituent molecules of sucrose. The glucose and fructose molecules are the ones which give the Fehling's test and the solution then turns brown.
Theoretically amylose is a reducing polysaccharide, because the anomeric carbon atom is at the end of the chain. Nevertheless as far as I know, due to the large molecular weight, the number of functional groups per gramm is too small to get a visible reduction of copper. In lactose (3:45) you can see that the anomeric carbon atom of the glucose is not connected to the galactose. So the ring is able to open, while the connection from the 4th carbon atom of the glucose to the 1st one of the galactose stays.
Thank you thank you so much! TBH i have learned more stuff about this experiment than in my class XD... i will recommend this vid to my teacher and hope she will learn something from it too (>-
It reacts with all kinds of reducing compounds and sugars. So it can't differentiate between aldoses and ketoses or other compounds like formaldehyde and acetaldehyde. To differentiate aldoses and ketoses the seliwanow test can be used.
Fehling's solution test-🤕🤒😞😖😭in this test aldehyde react with 2 molecules of copper sulphate and also with two molecules of sodium carbonate gives CO2 which is called as brick red precipitate with its byproducts carboxylic acid with 2 molecules sodium sulphate and 2 molecules of water
As you can hear I'm a non-native speaker and scientific language is even more difficult. So, I guess this happens quite often in my videos... My goal is that people understand what I'm talking about :)
Wonderful Demonstration as well as explanation!
super cool video!
the part about water bath was helpful. And also I didn't know about the toxicity of cuso4. Thank-you!
If you want to remind yourself of this easily, think of that among us task where you test 4 or 5 test tubes and they are all blue, when you check back on it one of them turns brick red, I never knew that was added in that game until when I first learnt about this
how do you remember the among us task
oooh yeaaah🤓😯🤗
@@averageanon007 He is an Among us kid
I could never complete that task actually
Thank you so much
This made easier to understand the test
Im doing this at the science month on 23 of november
Its proving glucose in honey and i need to explain everything that happeneds and why..the expiriment is a bit short so i wanted to see a video explanation so that i know more things that i can say there.Didnt see more than i knew but thanks!
Thank you sir
You made life easy
If we see all the organic reaction
pratically we an under stand better
Very good explanation
An excellent explanation.
great quality video
Great video
Good explanation and really helpful
Lots of information bro
This helped me a lot. Thank you!
it helps me a lot
Love u
great explanation...sir u made my day !!
Nice explaination
thank you
Why are Fehling’s A and B solutions made separately when they would be mixed afterwards?
It's just to increase shelf life. The complex would slowly decompose after a while, while these two solutions can be stored for months or even years.
so good!! this is what i need
thank you love u
Excuse me, can I ask you why the sucrose + citronensäure(citric acid anhydrous) mixture shows the color change?
I want to know the principles behind that.
If you can explain for me, I'd be very happy. fullofsoulman@gmail.com this is my e-mail address. You can send me an e-mail for additional explanation. Have a nice day ! :)
How thick do you have to be to write all that out instead of googling it yourself
It's been four years, but I'm writing so that someone else doesn't have to google. Basically, sucrose doesn't give the Fehling's test because the aldehyde group (-CHO) is locked up inside the ring due to the glycosidic bond formed. But this glycosidic bond can be broken up in acidic environments, so when the citric acid is added along with the sucrose, it breaks down into glucose and fructose, which are the constituent molecules of sucrose. The glucose and fructose molecules are the ones which give the Fehling's test and the solution then turns brown.
thanks a lot
Very nice.
Ty
Why fehling test doesn't give positive results with benzaldehyde؟؟؟answer the question please
Thank you so much
Very nice
Keep up man
well done
Thanku very much 😊😊
I smelled large amount of vapours of fehlings sol a+b+atetadehyde... Is it harmful
Thank you .
but you didn't told us if Aromatic Aldehydes give fehling test ?
But though explanation was nice i got it nd appreciate you
Lia qiao ...can yu tell me aboute Qualitative test name for monosacride oligosacrides and polysacrid i waiting fr yu
Thanks for the awesome video.
3rd one looks tasty
Really helped a lot
What about fructose content sir . How to find it ?
it is very nice and help full
Can you also explain the reaction if you add starch or lactose in a fehling's solution?
this is for my research x3
thanks inn advance
Theoretically amylose is a reducing polysaccharide, because the anomeric carbon atom is at the end of the chain. Nevertheless as far as I know, due to the large molecular weight, the number of functional groups per gramm is too small to get a visible reduction of copper. In lactose (3:45) you can see that the anomeric carbon atom of the glucose is not connected to the galactose. So the ring is able to open, while the connection from the 4th carbon atom of the glucose to the 1st one of the galactose stays.
Thank you thank you so much! TBH i have learned more stuff about this experiment than in my class XD...
i will recommend this vid to my teacher and hope she will learn something from it too (>-
You're welcome :D
Thanks
Amazing
brilliant
so cool man
Darun
Thank yooou it was helpful 😊
6. What are the disadvantages of Fehling's test
It reacts with all kinds of reducing compounds and sugars. So it can't differentiate between aldoses and ketoses or other compounds like formaldehyde and acetaldehyde. To differentiate aldoses and ketoses the seliwanow test can be used.
really helpful
thx a lot
Fehling's solution test-🤕🤒😞😖😭in this test aldehyde react with 2 molecules of copper sulphate and also with two molecules of sodium carbonate gives CO2 which is called as brick red precipitate with its byproducts carboxylic acid with 2 molecules sodium sulphate and 2 molecules of water
Thanks....... 🙏😇
Nice
teşekkürler organik kimya gecenin bu saatinde izlediğim videoya bak!!!
Thank you!!
how this occur
❤
Sir you explain in kannada please
in the form of reaction
RCHO+2CuSO4+2NaCO3=RCOOH+2Na2SO4+CO2+H2O
Please translate in hindi sir
I dont understand okeyyyyy
there's no such thing as splited**
As you can hear I'm a non-native speaker and scientific language is even more difficult. So, I guess this happens quite often in my videos... My goal is that people understand what I'm talking about :)
@@RaExpIn it's alright bro. As u can see, he liked his own comment. So no one agree with him
Thanks
thank you
❤