ing…Biochemicallypure–goesw/osayingWant>99%purity;?Nochanceif<97%Note–1-3%contaminantsdifficulttodetectInorderforcrystallizationtotakeplaceasolutionmustbesupersaturatedbyoneofthefollowing:-Cooling&temperaturereduction-Evaporationofsolvent-onception1.positionofasolutioncanbeexpressedinsomeways:Statetheweightofsolutepresentinagivenvolumeofsolution,convenientfortheanalyticalbutinconvenientinindustrialpractice.Statetheweightofsolutepresentinagivenweightofsolution,therelativeweightsofsoluteandsolventarenotexpressedprecisely.Solubility:statedasthepartsbyweightperpart(or100parts)byweightofsolvent.Thesoluteconcentrationshouldalwaysrefertotheanhydroussalt.onceptionSolubilitydiagramsshowsthetrendthatthesolubilityofasoluteinasolventchangeswithtemperature:SmoothcurvesUnevencurves:urrenceofphasechanges
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