Puas yog carboxylic acid react nrog 2 4 Dnph?
Puas yog carboxylic acid react nrog 2 4 Dnph?

Video: Puas yog carboxylic acid react nrog 2 4 Dnph?

Video: Puas yog carboxylic acid react nrog 2 4 Dnph?
Video: ALDEHYDES, KETONES AND CARBOXYLIC ACIDS in 150 minutes || Complete Chapter for NEET 2024, Kaum ib hlis
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2 , 4 - DNPH ua tsis yog teb nrog amides, esters los yog carboxylic acids . Raws li qhia hauv qab no rau cov ntaub ntawv ntawm ester, ib qho ntxiv resonance qauv tuaj yeem raug kos rau 3 hom kev sib xyaw ua ke piv rau ketone.

Raws li txoj cai, 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, hom tshuaj tiv thaiv dab tsi tshwm sim ntawm cov carbonyl compound thiab 2 4 Dinitrophenylhydrazine? Cov cov tshuaj tiv thaiv ntawm carbonyl compound thiab 2 , 4 -DNPH yog condensation, qhov twg ob qho tib si tshuaj sib xyaw ua ke thiab me me molecule H 2 O yog tshem tawm. Txhawm rau kos cov khoom yooj yim peb tuaj yeem taw tes rau carbonyl pab pawg ua haujlwm ntawm hydrazine functional pab pawg, ntim dej, thiab koom nrog 2 fragments ntawm C = N daim ntawv cog lus.

Yog li ntawd, qhov kev kuaj pom zoo 2/4 DNP qhia li cas?

2 , 4 - Dinitrophenylhydrazine tuaj yeem siv los txheeb xyuas qhov zoo ntawm carbonyl kev ua haujlwm ntawm ketone lossis aldehyde ua haujlwm pab pawg. A kuaj qhov zoo yog taw qhia los ntawm kev tsim cov daj, txiv kab ntxwv lossis liab precipitate (lub npe hu ua dinitrophenylhydrazone).

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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