ScienceHideout
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Problems with Fehling's Solution
In a lab activity I did, I used Fehling's solution to test for sugar. When I tested something with no sugar, nothing happened. But, when I tested
something with sugar, I got an orange precipitate.
Now- the problem- when I did a test with nothing at all, the solution decomposed and I got a brown precip.
How do I know if I really have sugar present, or if the solution is just decomposing?
Thanks,
ScienceHideout
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Hexavalent
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Benedict's solution is used for testing for reducing sugars, and gives an orange/brown ppt. when added.
How old were the solutions you used? IME we have always prepared Fehling's solution fresh in our labs.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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MR AZIDE
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Yeah, make up the solution fresh, then that way you know there is no contaminants, which is what i think must ve happened.
Its supposed to go from clear blue alkaline Cu2+ environment to red precipitate of copper(i) oxide while heating, when reducing sugars are present.
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