Puas yog formic acid muab 2/4 DNP kuaj?
Puas yog formic acid muab 2/4 DNP kuaj?

Video: Puas yog formic acid muab 2/4 DNP kuaj?

Video: Puas yog formic acid muab 2/4 DNP kuaj?
Video: Bruno Franco: A large source of formic acid in the atmosphere mediated by cloud droplets 2024, Kaum ib hlis
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Nws yog rau tus ib yam vim li cas koj ua tau Tsis ua amides los ntawm carboxylic kua qaub thiab amine: tus amine deprotonates cov kua qaub . Cov carboxylate anion yog resonance-stabilized thiab tus carbonyl cov pa roj carbon yog electrophilic tsis txaus. Vim li no, formic acid yuav tsis yog ua 2,4 - DNP test.

Ib yam li ib tug yuav nug, dab tsi reagents tuaj yeem cuam tshuam nrog 2 4 Dnph test?

Aldehydes thiab ketones hnov mob nrog 2, 4-dinitrophenylhydrazine reagent los ua daj, txiv kab ntxwv, lossis xim liab-txiv kab ntxwv precipitates, thaum cawv tsis hnov tsw. Kev tsim cov dej nag yog li ntawd qhia tias muaj aldehyde lossis ketone. Lub precipitate los ntawm qhov kev xeem no kuj ua hauj lwm raws li ib tug khoom derivative.

Ib yam li ntawd, nws txhais li cas yog tias cov nag lossis daus tsim hauv 2 4 DNP xeem yog daj? Brady tus xeem 2 , 4 - Dinitrophenylhydrazine tuaj yeem siv los ntsuas qhov zoo ntawm carbonyl functionality ntawm ketone lossis aldehyde functional pawg. Yog carbonyl compound yog aromatic, ces tus dej nag yuav ua liab; yog aliphatic, ces tus dej nag yuav muaj ib qho ntxiv daj xim.

Tom qab ntawd, ib tus tuaj yeem nug, puas yog carboxylic acid muab 2/4 DNP kuaj?

2 , 4 - DNPH ua tsis hnov mob nrog amides, esters lossis carboxylic acids . Raws li qhia hauv qab no rau tus rooj plaub ntawm ester, ib qho ntxiv resonance qauv ua tau tau kos rau 3 hom kev sib txuas no piv rau ketone.

Puas yog 2 4 Dinitrophenylhydrazine 2 4 DNP kuaj qhov txawv ntawm aldehydes thiab ketones?

Rau xeem rau ib aldehyde los yog ketone lub cev koj yuav siv 2 , 4 - dinitrophenylhydrazine ( 2 , 4 - DNP ). 2 , 4 - DNP tov nrog methanol thiab sulfuric acid yog paub raws li Brady's reagent. Yog hais tias ib tug silver grey khoom los yog daim iav zoo li cov nyhuv yog tsim, ib aldehyde yog tam sim no. Yog ib ketone lub cev yog tam sim no, muaj yuav yuav tsis muaj tshuaj tiv thaiv.

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