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Author: Subject: Copper Acetate preparation and Barfoed's reagent making.
vibbzlab
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[*] posted on 1-2-2020 at 17:55
Copper Acetate preparation and Barfoed's reagent making.



Copper acetate from home available chemicals and Performing Barfoed's test.

The procedure has been demonstrated in the video. If you want to directly proceed to the video check the link below.
Otherwise continue reading

You just need some copper metal
Vinegar ( acetic acid)
Peroxide (3% hydrogen peroxide) available in medical supplies store
Glucose is also available from supermarket.

If you have an access to glacial acetic acid and 30% hydrogen peroxide like I have done,it would be much faster.

For this experiment I have used
4g of copper metal
20ml of glacial acetic acid and
Almost the same amount of 30%hydrogen peroxide
I didn't look exactly to the concentration of hydrogen peroxide but it was really interesting to see the copper reacting with the acetic acid like magnesium metal ribbon in acid. It was too intense that I had to change my small beaker to a larger one.
After complete reaction I was left with a blue solution which is the copper acetate.
I then boiled down the solution to crystallise the compound.

Barfoed's Reagent
Preparation
Take 1g of copper acetate
Add 18ml of distilled water
Dissolve the salt and then add 1ml of glacial acetic acid and warm the solution.

Test .
Barfoed's test can differentiate between monosaccharides and disaccharides and has been included in the qualitative analysis of carbohydrates

Procedure
To 5 ml of Barfoed’s reagent add 2 ml of sample solution, Keep in boiling water bath for exactly 2 min

Observations
Fine red ppt. clinging to the walls of the test tube; some settles down on cooling.

Inference
Monosaccharides reduces Cu2+ to Cu1+ in acidic medium on boiling water bath for 2 min

A point to note is that Barfoed’s test depends on the concentration of sugar solution and the time of boiling also. A 5% disaccharides will also give Barfoed’s test positive.

Now to see the full video check the link below
https://youtu.be/JwHkiQ-1y7M

Picture shows the crystals of copper acetate



IMG_20200201_130357_029.jpg - 256kB





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Have a small cute home chemistry lab.


Please do check out my lab in YouTube link below

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