Extraction yog ib chav ua haujlwm uas cais cov sib tov los ntawm kev siv cov solubilities sib txawv ntawm cov khoom hauv cov kuab tshuaj. Tshwj xeeb, nws siv qhov sib txawv ntawm solubility los yog muab faib coefficients ntawm ib yam khoom nyob rau hauv ob immiscible (los yog me ntsis soluble) cov kuab tshuaj los hloov cov kuab tshuaj los ntawm ib qho hnyav mus rau lwm qhov. Los ntawm kev rov qab rho tawm, feem ntau ntawm cov compound yog muab rho tawm. Qhov ntau dua qhov sib txawv ntawm kev faib coefficients ntawm cov khoom hauv ob theem hnyav, qhov kev sib cais ntau dua.
Extraction tuaj yeem yog lub cev lossis tshuaj lom neeg, nyob ntawm seb puas muaj tshuaj lom neeg tshwm sim thaum lub sijhawm rho tawm. Extraction yog ib txoj kev siv nyob rau hauv cov organic chemistry laboratories los purify thiab refine compounds. Los ntawm kev rho tawm, cov khoom xav tau tuaj yeem muab rho tawm los ntawm cov khoom sib tov los yog kua.