Difference between revisions of "Fehling's solution"

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(Preparation)
(Preparation)
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*Fehling's "A" uses 7 g CuSO4.5H2O dissolved in distilled water containing 2 drops of dilute sulfuric acid.
 
*Fehling's "A" uses 7 g CuSO4.5H2O dissolved in distilled water containing 2 drops of dilute sulfuric acid.
 
*Fehling's "B" uses 35g of potassium tartrate and 12g of NaOH in 100 ml of distilled water.
 
*Fehling's "B" uses 35g of potassium tartrate and 12g of NaOH in 100 ml of distilled water.
 +
These two solutions should be stoppered and stored until needed.
 +
 +
For the test:
 +
Mix 15 ml of solution-"A" with 15 ml of solution-"B"
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Add 2 ml of this mixture to an empty test tube.
 +
Add 3 drops of the compound to be tested to the tube.
 +
Place the tube in a water-bath at 60° C.
 +
 +
A positive test is indicated by a green suspension and a red precipitate
  
 
==Projects==
 
==Projects==

Revision as of 18:01, 7 February 2016

Fehling's solution
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Fehling's solution is the name given to a chemical reagent, primarily used to differentiate between water-soluble carbohydrate and ketone functional groups. It can also be used as a test for reducing sugars and non reducing sugars. This reagent is prepared from two solutions, a basic solution of Rochelle Salt and a solution of Copper Sulfate.

Properties

Chemical

Physical

Availability

Delete this section if not applicable

Preparation

  • Fehling's "A" uses 7 g CuSO4.5H2O dissolved in distilled water containing 2 drops of dilute sulfuric acid.
  • Fehling's "B" uses 35g of potassium tartrate and 12g of NaOH in 100 ml of distilled water.

These two solutions should be stoppered and stored until needed.

For the test: Mix 15 ml of solution-"A" with 15 ml of solution-"B" Add 2 ml of this mixture to an empty test tube. Add 3 drops of the compound to be tested to the tube. Place the tube in a water-bath at 60° C.

A positive test is indicated by a green suspension and a red precipitate

Projects

Handling

Safety

Storage

Disposal

References

Relevant Sciencemadness threads