Puas muaj ntxhiab aldehydes muab Fehling kuaj?
Puas muaj ntxhiab aldehydes muab Fehling kuaj?

Video: Puas muaj ntxhiab aldehydes muab Fehling kuaj?

Video: Puas muaj ntxhiab aldehydes muab Fehling kuaj?
Video: Vauv deev yuam kev niam tais #2, 1/4/2018 2024, Kaum ib hlis
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Fehling's Test & Fehling tus Reagent

Cov tshuaj tiv thaiv yuav tsum tau cua sov ntawm aldehyde nrog Fehling tus Reagent uas yuav tshwm sim nyob rau hauv tsim ntawm reddish-xim av xim precipitate. Yog li, cov tshuaj tiv thaiv ua rau tsim cov carboxylate anion. Txawm li cas los xij, aromaticaldehydes ua tsis teb rau Fehling'sTest.

Ib yam li ntawd, koj tuaj yeem nug, puas muaj ntxhiab aldehydes muab cov tshuaj tollens?

Tollens xeem yog muab los ntawm aldehydes suav nrog ob leeg aromatic thiab aliphatic aldehydes . Whereas fehlings yog txo los ntawm tsuas yog aliphatic aldehyde . Aromatic aldehydes ua tsis qhia qhov tshuaj tiv thaiv no. Tab sis nws formsilver iav nrog Tollen tus reagent.

Tom qab, lo lus nug yog, yog vim li cas aromatic aldehydes tsis muab Fehling qhov kev sim? Hauv aromatic aldehydes , pawg CHO yog txuas rau lub nplhaib benzene. Vim yog resonance, carbonyl pawg 's C tau txais daim ntawv cog lus ob zaug nrog cov benzene uas muaj zog heev. oxidizing cov neeg ua haujlwm zoo li Cu2 + tsis tuaj yeem rhuav tshem cov ntawv cog lus, sosuch aldehydes tsis muaj peev xwm qhia tau fehling 's xeem.

Tsis tas li ntawd, puas muaj ntxhiab aldehydes muab Benedict qhov kev sim?

yuav aromatic aldehydes muab benedict qhov kev sim . Nyob zoo cov tub kawm, Lub xeem muab tsis muaj liab precipitateCu2O raws li nws tshwm tsuas yog rau aliphatic aldehydes , yog li no xeem yog siv los sib txawv aliphatic thiab aromatic hydrocarbon. (Ketones ua tsis teb rau qhov no xeem ).

Kev kuaj Fehling puas tuaj yeem siv los paub qhov txawv ntawm aldehyde thiab ketone?

Fehling tus daws ua tau ua siv los paub qhov txawv aldehyde vs ketone lub cev pab pawg ua haujlwm. Thecompound yuav tsum tau kuaj yog ntxiv rau lub Fehling tus tov thiab sib tov yog rhuab. Aldehydes yog oxidized, muab apositive tshwm sim, tab sis ketones ua tsis hnov tsw, tshwj tsis yog lawv yog α-hydroxy ketones.

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