Nyob rau hauv ib txwm-theem chromatography, qhov tsawg tshaj plaws polar compounds elute ua ntej thiab feem ntau polar compounds elute kawg. Cov theem ntawm lub xov tooj ntawm tes muaj cov kuab tshuaj tsis muaj polar xws li hexane lossis heptane tov nrog me ntsis ntxiv polar hnyav xws li isopropanol, ethyl acetate lossis chloroform.
Yuav ua li cas koj qhia qhov twg yuav elute ua ntej?
Ib tug tsis muaj zog polar hnyav yuav zoo li elute qhov tsawg polar molecules ua ntej. Yog li, hexanetej zaum yuav yog thawj tus neeg tau txais txiaj ntsig, vim tias alkanes yog qhov qis dua polar dua alkenes.
Yuav ua li cas thiaj li yuav tsum cov khoom sib txuas tawm ntawm kab?
- Nyob rau hauv ib kem ib txwm, cov theem nyob ruaj khov yog ntau dua polar dua li theem mobile. …
- Nyob rau hauv ib kem ib txwm, peb lub tebchaw tau eluted nyob rau hauv raws li nram no: p-dimethylbenzene, p-dimethoxybenzene, ces p-methoxyphenol.
Yuav ua li cas cov compound yuav elute ua ntej hauv roj chromatography?
Qhov kev txiav txim ntawm elution thaum siv polydimethyl siloxane feem ntau ua raws cov ntsiab lus kub ntawm cov kua dej, nrog qis boiling solutes eluting thawj. Hloov qee cov methyl pawg nrog rau lwm cov khoom siv ntxiv ua rau cov theem nyob ruaj khov polarity thiab muab kev xaiv ntau dua.
Cov tebchaw twg yuav elute thawj zaug hauv theem rov qab HPLC?
Txoj kev hloov pauv polarity sib cais no yog hu ua gradient. Nrog rau qhov thim rov qab-theem gradient, cov cov khoom sib xyaw nrog ntau dua solubility hauv dej eluteua ntej.
