It may be that there wasn't enough acetaldehyde added and so the reaction is incomplete. The final product should be orange brown, so you're almost there.
Another possibility is that acetaldehyde may polymerize to a resinous product if there is excess of sodium hydroxide in Fehling's solution.
Anyone who has better answers please comment, thanks.
nice taught alot
MultiBeenish 1 year ago
Good video and description, 5 starts!
Was acctually just studying 3 tests for aldehydes a week ago for chemistry exam:
1. Potassium Dichromate turns orange to green,
2. Fehling's Solution turns blood red,
3. Tollens Reagent (ammonical AgNO3) form's a ''silver mirror'' of precipitated silver.
MariusSemeonOrtiz 2 years ago 3
is this like benedict's solution?
trarthas91 3 years ago
yeh it is !
idiotkrati 3 years ago
Did you have Cu2+(aq) in the solution ? And you god it redusated by using flame, so it became Cu2O ?
Where on the aldehyde is the Cu2+ ?
Thank you so much for the video.
idiotkrati 3 years ago
I did the same experiment but with acetaldehyde(ethanal)and the solution went green then to a yellow/brown precipitate. Anyone know why!
Ortilochus 3 years ago
It may be that there wasn't enough acetaldehyde added and so the reaction is incomplete. The final product should be orange brown, so you're almost there.
Another possibility is that acetaldehyde may polymerize to a resinous product if there is excess of sodium hydroxide in Fehling's solution.
Anyone who has better answers please comment, thanks.
evansp12 3 years ago
Thanks for for the explanation.
Ortilochus 3 years ago
I agree with evansp, bt it may be hydrated copper(I) oxide.
slateflash 3 years ago