fourth commiss direct octob approxim law member state relat method analysi check composit cosmet product eec commiss european commun regard treati establish european econom commun regard council direct eec juli approxim law member state relat cosmet product amend direct eec articl thereof direct eec offici test cosmet product aim ensur condit laid commun provis composit cosmet product satisfi method analysi laid quickli step attain object definit method commiss direct eec eec eec fourth step consist definit method identif determin glycerol aminobenzo determin chlorobutanol identif determin quinin identif determin inorgan sulphit hydrogen sulphit identif determin chlorat alkali metal identif determin sodium iodat measur provid direct accord opinion committe adapt direct eec technic progress adopt direct articl member state step ensur offici test cosmet product identif determin glycerol aminobenzo determin chlorobutanol identif determin quinin identif determin inorgan sulphit hydrogen sulphit identif determin chlorat alkali metal identif determin sodium iodat perform accord method annex articl member state bring forc law regul administr provis compli direct decemb forthwith inform commiss thereof articl direct address member state brussel octob commiss stanlei clinton davi member commiss oj oj oj oj oj annex identif determin glycerol aminobenzo identif scope field applic method detect alpha monoglyceryl aminobenzo glycerol aminobenzo detect ethyl aminobenzo benzocain inn present impur principl identif thin layer chromatographi silica gel fluoresc indic detect free primari amin group format diazo dye plate reagent reagent analyt puriti solvent mixtur cyclohexan propan ol stabil dichloromethan develop solvent petroleum ether benzen aceton ammonium hydroxid solut minimum nh develop solut sodium nitrit ml hydrochlor acid prepar immedi naphthol ml potassium hydroxid standard solut alpha monoglyceryl aminobenzo ml mix solvent ethyl aminobenzo ml mix solvent silica gel plate mm thick mm mm apparatu normal apparatu thin layer chromatographi ultrason vibrat millipor filter fh mm equival procedur sampl prepar weigh product analyz ml stopper graduat flask make mark solvent stopper leav hour room temperatur ultrason vibrat filter millipor filter filtrat chromatographi thin layer chromatographi deposit sampl solut standard solut plate develop chromatogram height mm tank previous satur solvent plate dry ambient temperatur develop observ plate nm uv light sprai complet dri plate solut dry room temperatur minut immedi sprai solut dry plate oven spot orang colour alpha monoglyceryl aminobenzo rf ethyl aminobenzo rf determin scope field applic method determin alpha monoglyceryl aminobenzo determin ethyl aminobenzo determin alpha monoglyceryl aminobenzo ethyl aminobenzo definit alpha monoglyceryl aminobenzo ethyl aminobenzo content measur method express percentag mass product principl product analyz suspend methanol treatment sampl determin high perform liquid chromatographi hplc reagent reagent analyt puriti suitabl hplc methanol potassium dihydrogenorthophosph kh po zinc di acet zn ch coo acet acid tetrapotassium hexacyanoferr fe cn ethyl hydroxybenzo alpha monoglyceryl aminobenzo ethyl aminobenzo phosphat buffer solut dissolv potassium dihydrogenorthophosph litr water eluant phosphat buffer solut methanol composit mobil phase chang order achiev resolut factor retent time minut peak peak width half height milimetr chart speed millimetr minut stock solut alpha monoglyceryl aminobenzo weigh accur mg alpha monoglyceryl aminobenzo introduc ml graduat flask dissolv ml methanol make mark buffer solut mix stock solut ethyl aminobenzo weigh accur mg ethyl aminobenzo introduc ml graduat flask dissolv ml methanol make mark buffer solut mix intern standard solut weigh accur mg ethyl hydroxybenzo transfer ml standard flask dissolv ml methanol make mark buffer solut mix standard solut prepar standard solut dissolv ml eluant tabl standard solut alpha monoglyceryl aminobenzo ethyl aminobenzo ethyl hydroxybenzo mg ml ml mg ml ml mg ml ml ii iii iv valu indic correspond exact mass nb solut prepar carrez solut dissolv tetrapotassium hexacyanoferr water make ml carrez ii solut dissolv zinc di acet ml acet acid water make ml merck lichrosorb rp equival averag particl size mm apparatu usual laboratori equip high perform chromatographi equip variabl wavelength uv detector thermostat chamber set stainless steel column length mm intern diamet mm pack lichrosorb rp ultrason bath procedur sampl prepar weigh accur sampl ml beaker add ml methanol place beaker ultrason bath minut produc suspens transfer suspens obtain quantit ml standard flask ml eluant add success ml carrez solut ml carrez ii solut mix addit make mark eluant mix filter pleat filter paper pipett transfer ml filtrat obtain ml intern standard solut ml standard flask make mark eluant mix solut obtain carri chromatographi analysi chromatographi adjust flow rate mobil phase ml min set column temperatur set detector nm microsyring inject time ml solut chromatograph measur area peak calibr curv inject ml standard solut measur peak area concentr calcul ratio peak area alpha monoglyceryl aminobenzo peak area intern standard plot ratio abscissa ordin ratio mass proce manner ethyl hydroxybenzo calcul calibr curv obtain read mass ratio rp rp ratio area peak calcul rp mass alpha monoglyceryl aminobenzo mass ethyl hydroxybenzo rp mass ethyl aminobenzo mass ethyl hydroxybenzo mass ratio obtain calcul alpha monoglyceryl aminobenzo ethyl aminobenzo content mass percentag formula rp alpha monoglyceryl aminobenzo rp rp ethyl aminobenzo rp quantiti ethyl hydroxybenzo intern standard weigh milligram quantiti sampl gram weigh repeat content alpha monoglyceryl aminobenzo differ result parallel determin carri sampl exce content ethyl aminobenzo differ result parallel determin carri sampl exce note carri analysi check sampl substanc overlap peak intern standard ethyl aminobenzo chromatogram order check absenc interfer repeat determin chang proport methanol mobil phase rel determin chlorobutanol scope field applic method suitabl determin chlorobutanol inn maximum concentr cosmet product aerosol definit content chlorobutanol measur method express percentag mass product principl treatment product analyz determin ga chromatographi trichloroethanol intern standard reagent reagent analyt puriti chlorobutanol trichloro methylpropan ol trichloroethanol absolut ethanol standard solut chlorobutanol ml ethanol standard solut trichloroethanol mg ml ethanol apparatu normal laboratori equip ga chromatograph electron detector ni procedur prepar sampl weigh accur sampl place ml volumetr flask dissolv ethanol add ml intern standard solut make mark ethanol iso ga chromatographi condit oper condit yield resolut factor retent time minut peak peak width half height millimetr chart speed millimetr minut exampl oper condit provid requir resolut column ii materi glass stainless steel length diamet mm mm stationari phase carbowax tpa gaschrom mesh ov chromosorb waw dmc mesh condit dai temperatur injector column detector carrier ga nitrogen argon methan flowrat ml min ml min standard curv ml volumetr flask add ml standard solut ml solut make mark ethanol mix inject ml solut chromatograph accord oper condit construct calibr curv plot abscissa ratio mass chlorobutanol trichloroethanol ordin ratio peak area inject ml solut obtain proce condit calcul calcul standard curv quantiti express mg chlorobutanol solut content chlorobutanol sampl calcul formula chlorobutanol repeat chlorobutanol content differ result determin parallel carri sampl exce note result equal exce maximum permit concentr check absenc interfer iso identif determin quinin identif scope field applic method intend detect presenc quinin shampoo hair lotion principl identif thin layer chromatographi silica gel detect quinin blue fluoresc quinin acid condit nm confirm fluoresc elimin bromin vapour ammonia vapour yellowish fluoresc reagent reagent analyt puriti silica gel plate fluoresc indic mm thick mm mm develop solvent toluen diethyl ether dichloromethan diethylamin methanol sulphur acid diethyl ether develop agent carefulli add ml sulphur acid ml diethyl ether cool contain bromin ammonium hydroxid solut quinin anhydr standard solut weigh accur mg anhydr quinin standard flask dissolv ml methanol apparatu normal equip thin layer chromatographi ultrason bath millipor filter fh equival suitabl filtrat equip procedur prepar sampl weigh accur quantiti sampl approxim mg quinin ml standard flask dissolv make mark methanol stopper flask leav hour room temperatur ultrason vibrat filter filtrat chromatographi thin layer chromatographi deposit ml standard solut ml sampl solut silica gel plate develop chromatogram distanc mm solvent tank previous satur solvent develop dry plate room temperatur sprai reagent leav plate dry hour room temperatur observ light uv lamp adjust wavelength nm quinin appear fluoresc intens blue spot tabl valu rf main alkaloid relat quinin develop solvent alkaloid rf quinin quinidin cinchonin cinchonidin hydroquinidin confirm quinin present plate expos approxim hour bromin vapour fluoresc disappear plate expos ammonia vapour spot reappear brown colour plate examin uv light nm yellowish fluoresc observ detect limit mg quinin determin scope field applic method describ determin quinin determin maximum permit concentr shampoo hair lotion definit quinin content determin method express percentag mass product principl treatment product analyz determin high perform liquid chromatographi hplc reagent reagent analyt puriti suitabl hplc acetonitril potassium dihydrogenorthophosph kh po orthophosphor acid tetramethylaminium bromid quinin anhydr methanol orthophosphor acid solut weigh orthophosphor acid dissolv nl water graduat flask potassium dihyrogenorthophosph solut weigh potassium dihydrogenorthophosph dissolv ml water graduat flask tetramethylammonium bromid solut dissolv tetramethylammonium bromid ml water graduat flask eluant orthophosphor acid potassium dihydrogenorthophosph tetramethylammonium bromid water acetonitril composit mobil phase chang order achiev resolut factor retent time minut peak peak width half height millimetr chart speed millimetr minut silica treat octadecylsilan mm standard solut weigh accur approxim mg quinin anhydr set ml standard flask make mark methanol shake content flask quinin dissolv filter sampl mm filter apparatu usual laboratori equip ultrason bath high perform liquid chromatographi equip variabl wavelength detector column length mm intern diamet mm fill silica millipor filter fh mm equival suitabl filtrat apparatu procedur sampl prepar weigh accur ml standard flask quantiti product suffici mg anhydr quinin add ml methanol place flask ultrason bath minut make mark methanol mix solut filter aliquot chromatographi flowrat ml min detector wavelength nm inject volum ul filter solut measur peak area calibr curv inject time ml refer solut measur area peak calcul averag area concentr produc calibr curv verifi rectilinear calcul calibr curv determin quantiti mg anhydr quinin present volum inject concentr anhydr quinin sampl percentag mass obtain formula anhydr quinin quantiti microgram anhydr quinin determin microlitr filter solut mass sampl gram repeat anhydr quinin content differ result determin perform parallel sampl exce anhydr quinin content differ result determin perform parallel sampl exce identif determin inorgan sulphit hydrogen sulphit scope field applic method describ identif determin inorgan sulphit hydrogen sulphit cosmet product applic product aqueou alcohol phase concentr sulphur dioxid identif principl sampl heat hydrochlor acid sulphur dioxid liber identifi odour effect indic paper reagent reagent analyt puriti hydrochlor acid potassium iodat starch paper suitabl altern apparatu normal laboratori equip flask ml fit short reflux condens procedur place sampl flask ml hydrochlor acid mix heat boil test emiss sulphur iso determin definit sulphit hydrogen sulphit content sampl determin method express percentag mass sulphur dioxid principl acidif sampl sulphur dioxid liber distil solut hydrogen peroxid sulphur acid form titrat standard sodium hydroxid solut reagent reagant analyt puriti hydrogen peroxid prepar daili orthophosphor acid methanol sodium hydroxid standard solut nitrogen indic mixtur methyl red ethanol methylen blue ethanol filter solut apparatu normal laboratori equip distil apparatu figur procedur weigh accur sampl distil flask figur add ml water ml methanol mix place ml hydrogen peroxid ml water drop indic distil receiv figur add drop sodium hydroxid indic turn green repeat wash bottl figur assembl apparatu adjust nitrogen flow bubbl minut run ml orthophosphor acid funnel distil flask heat rapidli boil simmer gentli total time minut detach distil receiv rins tube titrat sodium hydroxid solut indic turn green calcul calcul content sulphit hydrogen sulphit mass sampl expresss sulphur dioxid mv molar concentr sodium hydroxid solut volum sodium hydroxid requir titrat millilitr mass sampl gram repeat content sulphur dioxid differ parallel determin sampl greater dioxid smell indic paper iso sulphurdioxid distil apparatu tanner dimens mm identif determin chlorat alkali metal scope field applic method describ identif determin chlorat toothpast cosmet product identif principl chlorat separ halat thin layer chromatographi identifi oxid iodid form iodin reagent reagent analyt puriti refer solut aqueou solut potassium chlorat bromat iodat prepar freshli develop solvent ammonia solut aceton butanol potassium iodid aqueou solut starch solut hydrochlor acid readi cellulos thin layer plate mm apparatu normal equip thin layer chromatographi procedur extract sampl water filter dilut ml deposit ml plate solut ml aliquot refer solut place plate tank develop ascend chromatographi quarter length plate solvent remov tank solvent evapor nb hour sprai plate potassium iodid dry minut sprai plate starch solut dry minut sprai plate hydrochlor acid evalu chlorat present blue spot possibl brown spot half hour rf approxim halat rf iodat bromat chlorat note bromat iodat give reaction care confus spot bromat chlorat determin definit chlorat content sampl determin method express percentag mass chlorat principl chlorat reduc zinc powder acid condit form chlorid measur potentiometr titrat silver nitrat solut similar determin reduct permit presenc halid reagent reagent analyt puriti acet acid zinc powder silver nitrat standard solut apparatu normal laboratori equip potentiomet equip silver indic electrod procedur sampl prepar weigh accur quantiti approxim centrifug tube add ml acet acid mix carefulli wait minut centrifug minut rev min transfer supernat solut ml volumetr flask repeat centrifug ad ml acet acid residu collect solut chlorat volumetr flask fill mark acet acid reduct chlorat ml solut add zinc powder bring boil flask fit condens tube minut boil cool filter rins flask water filter combin filtrat rise determin chlorid titrat ml solut silver nitrat potentiomet titrat ml solut silver nitrat nb product bromin iodin deriv releas bromid iodid reduct titrat curv inflexion point case volum titrat solut chlorid differ penultim inflexion point calcul content chlorat sampl calcul formula chlorat clo volum millilitr silver nitrat solut titrat solut volum millilitr silver nitrat solut titrat millilitr solut molal silver nitrat standard solut mass sampl gram repeat chlorat content differ result determin carri parallel sampl iso identif determin sodium iodat scope field applic method describ procedur identifi determin rins cosmet product sodium iodat identif principl sodium iodat separ halat thin layer chromatographi identifi oxid iodid form iodin reagent reagent analyt puriti refer solut aqueou solut potassium chlorat bromat iodat prepar freshli develop solvent ammonia solut aceton butanol potassium iodid aqueou solut starch solut hydrochlor acid apparatu readi cellulos thin layer chromatographi mm plate normal equip thin layer chromatographi procedur extract sampl water filter dilut ml deposit ml solut base line plate ml aliquot refer solut place plate tank develop ascend chromatographi quarter length plate solvent remov plate tank solvent evapor ambient temparatur nb hour sprai plate potassium iodid dry minut sprai starch dry minut final sprai hydrochlor evalu iodat present blue spot colour brown brown stand immedi rf approxim note bromat give reaction rf valu approxim chlorat minut rf valu determin definit sodium iodat content determin method express percentag mass sodium iodat principl sodium iodat dissolv water determin mean high perform liquid chromatographi seri revers phase column anion exchang column reagent reagent analyt puriti suitabl high perform liquid chromatographi hplc hydrochlor acid sodium sulphit aq sodium iodat stock solut prepar stock solut mg sodium iodat ml water potassium dihydrogenorthophosph disodium hydrogenorthophosph hplc mobil phase dissolv potassium dihydrogenorthophosph disodium hydrogenorthophosph litr water ph result solut univers indic paper ph apparatu ordinari laboratori apparatu circular filter paper diamet mm schleicher schuell equival high perform liquid chromatograph variabl wavelength detector column length mm intern diamet mm number connect seri column necleosil equival column vydac tm sb equival procedur sampl prepar fluid sampl shampoo weigh accur test portion approxim sampl ml glass stopper calibr tube measur flask fill mark water mix filter solut determin iodat solut mean hplc section solid sampl soap fine divid part sampl weigh accur test portion approxim ml glass stopper measur cylind fill ml water shake vigor minut centrifug filter filter paper mixtur stand night shake jellylik solut vigor filter filter paper determin iodat filtrat mean hplc section chromatographi flowrat ml min detector wavelength nm inject volum ml measur peak area calibr pipett ml sodium iodat stock solut ml volumetr flask fill mark mix solut obtain mg sodium iodat ml inject ml portion standard iodat solut liquid chromatograph obtain chromatogram determin peak area iodat plot curv relat peak area sodium iodat concentr calcul calcul sodium iodat content percentag mass formula sodium iodat vc mass gram test portion total volum sampl solut millilitr obtain concentr milligram millilitr sodium iodat obtain calibr curv repeat sodium iodat content differ result parallel determin carri sampl exce confirm principl acidifi solut cosmet product iodat io reduc iodid sulphit result solut investig mean hplc peak retent time retent time iodat disappear treatment sulphit origin peak attribut iodat procedur pipett ml portion sampl solut obtain section conic flask adjust ph solut lower hydrochlor acid univers indic paper add drop sodium sulphit solut mix inject ml portion solut liquid chromatograph compar chromatogram chromatogram obtain paragraph sampl exce iso principl treatment product analyz determin ga chromatographi trichloroethanol intern standard reagent reagent analyt puriti chlorobutanol trichloro methylpropan ol trichloroethanol absolut ethanol standard solut chlorobutanol ml ethanol standard solut trichloroethanol mg ml ethanol apparatu normal laboratori equip ga chromatograph electron detector ni procedur prepar sampl weigh accur sampl place ml volumetr flask dissolv ethanol add ml intern standard solut make iso ga chromatographi condit oper condit yield resolut factor retent time minut peak peak width half height millimetr chart speed millimetr minut exampl oper condit provid requir resolut column ii materi glass stainless steel length diamet mm mm stationari phase carbowax tpa gaschrom mesh ov chromosorb waw dmc mesh condit dai temperatur injector column detector carrier ga nitrogen argon methan flowrat ml min ml min standard curv ml volumetr flask add ml standard solut ml solut make mark ethanol mix inject solut chromatograph accord oper condit construct calibr curv plot abscissa ratio mass chlorobutanol trichloroethanol ordin ratio peak area inject solut obtain proce condit calcul calcul standard curv quantiti quot express chlorobutanol solut content chlorobutanol sampl calcul formula chlorobutanol repeat chlorobutanol content differ result determin parallel carri sampl exce note result equal exce maximum permit concentr check absenc interfer mark ethanol iso identif determin quinin identif scope field applic method intend detect presenc quinin shampoo hair lotion principl identif thin layer chromatographi silica gel detect quinin blue fluoresc quinin acid condit nm confirm fluoresc elimin bromin vapour ammonia vapour yellowish fluoresc reagent reagent analyt puriti silica gel plate fluoresc indic mm thick mm mm develop solvent toluen diethyl ether dichloromethan diethylamin methanol sulphur acid diethyl ether develop agent carefulli add ml sulphur acid ml diethyl ether cool contain bromin ammonium hydroxid solut quinin anhydr standard solut weigh accur mg anhydr quinin standard flask dissolv ml methanol apparatu normal equip thin layer chromatographi ultrason bath millipor filter fh equival suitabl filtrat equip procedur prepar sampl weigh accur quantiti sampl approxim mg quinin ml standard flask dissolv make mark methanol stopper flask leav hour room temperatur ultrason vibrat filter filtrat chromatographi thin layer chromatographi deposit standard solut sampl solut silica gel plate develop chromatogram distanc mm solvent tank previous satur solvent develop dry plate room temperatur sprai reagent leav plate dry hour room temperatur observ light uv lamp adjust wavelength nm quinin appear fluoresc intens blue spot tabl valu rf main alkaloid relat quinin develop solvent alkaloid rf quinin quinidin cinchonin cinchonidin hydroquinidin confirm quinin present plate expos approxim hour bromin vapour fluoresc disappear plate expos ammonia vapour spot reappear brown colour plate examin uv light nm yellowish fluoresc observ detect limit quinin determin scope field applic method describ determin quinin determin maximum permit concentr shampoo hair lotion definit quinin content determin method express percentag mass product principl treatment product analyz determin high perform liquid chromatographi hplc reagent reagent analyt puriti suitabl hplc acetonitril potassium dihydrogenorthophosph kh po orthophosphor acid tetramethylaminium bromid quinin anhydr methanol orthophosphor acid solut weigh orthophosphor acid dissolv nl water graduat flask potassium dihyrogenorthophosph solut weigh potassium dihydrogenorthophosph dissolv ml water graduat flask tetramethylammonium bromid solut dissolv tetramethylammonium bromid ml water graduat flask eluant orthophosphor acid potassium dihydrogenorthophosph tetramethylammonium bromid water acetonitril composit mobil phase chang order achiev resolut factor retent time minut peak peak width half height millimetr chart speed millimetr minut silica treat octadecylsilan standard solut weigh accur approxim mg quinin anhydr set ml standard flask make mark methanol shake content flask quinin dissolv filter sampl filter apparatu usual laboratori equip ultrason bath high perform liquid chromatographi equip variabl wavelength detector column length mm intern diamet mm fill silica millipor filter fh equival suitabl filtrat apparatu procedur sampl prepar weigh accur ml standard flask quantiti product suffici mg anhydr quinin add ml methanol place flask ultrason bath minut make mark methanol mix solut filter aliquot chromatographi flowrat ml min detector wavelength nm inject volum ul filter solut measur peak area calibr curv inject time refer solut measur area peak calcul averag area concentr produc calibr curv verifi rectilinear calcul calibr curv determin quantiti anhydr quinin present volum inject concentr anhydr quinin sampl percentag mass obtain formula anhydr quinin quantiti microgram anhydr quinin determin microlitr filter solut mass sampl gram repeat anhydr quinin content differ result determin perform parallel sampl exce anhydr quinin content differ result determin perform parallel sampl exce identif determin inorgan sulphit hydrogen sulphit scope field applic method describ identif determin inorgan sulphit hydrogen sulphit cosmet product applic product aqueou alcohol phase concentr sulphur dioxid identif principl sampl heat hydrochlor acid sulphur dioxid liber identifi odour effect indic paper reagent reagent analyt puriti hydrochlor acid potassium iodat starch paper suitabl altern apparatu normal laboratori equip flask ml fit short reflux condens procedur place sampl flask ml hydrochlor acid mix heat boil test emiss sulphur dioxid smell iso determin definit sulphit hydrogen sulphit content sampl determin method express percentag mass sulphur dioxid principl acidif sampl sulphur dioxid liber distil solut hydrogen peroxid sulphur acid form titrat standard sodium hydroxid solut reagent reagant analyt puriti hydrogen peroxid prepar daili orthophosphor acid methanol sodium hydroxid standard solut nitrogen indic mixtur methyl red ethanol methylen blue ethanol filter solut apparatu normal laboratori equip distil apparatu figur procedur weigh accur sampl distil flask figur add ml water ml methanol mix place ml hydrogen peroxid ml water drop indic distil receiv figur add drop sodium hydroxid indic turn green repeat wash bottl figur assembl apparatu adjust nitrogen flow bubbl minut run ml orthophosphor acid funnel distil flask heat rapidli boil simmer gentli total time minut detach distil receiv rins tube titrat sodium hydroxid solut indic turn green calcul calcul content sulphit hydrogen sulphit mass sampl expresss sulphur dioxid mv molar concentr sodium hydroxid solut volum sodium hydroxid requir titrat millilitr mass sampl gram repeat content sulphur dioxid differ parallel determin sampl greater indic paper iso sulphurdioxid distil apparatu tanner dimens mm identif determin chlorat alkali metal scope field applic method describ identif determin chlorat toothpast cosmet product identif principl chlorat separ halat thin layer chromatographi identifi oxid iodid form iodin reagent reagent analyt puriti refer solut aqueou solut potassium chlorat bromat iodat prepar freshli develop solvent ammonia solut aceton butanol potassium iodid aqueou solut starch solut hydrochlor acid readi cellulos thin layer plate mm apparatu normal equip thin layer chromatographi procedur extract sampl water filter dilut ml deposit plate solut aliquot refer solut place plate tank develop ascend chromatographi quarter length plate solvent remov tank solvent evapor nb hour sprai plate potassium iodid dry minut sprai plate starch solut dry minut sprai plate hydrochlor acid evalu chlorat present blue spot possibl brown spot half hour rf approxim halat rf iodat bromat chlorat note bromat iodat give reaction care confus spot bromat chlorat determin definit chlorat content sampl determin method express percentag mass chlorat principl chlorat reduc zinc powder acid condit form chlorid measur potentiometr titrat silver nitrat solut similar determin reduct permit presenc halid reagent reagent analyt puriti acet acid zinc powder silver nitrat standard solut apparatu normal laboratori equip potentiomet equip silver indic electrod procedur sampl prepar weigh accur quantiti quot approxim centrifug tube add ml acet acid mix carefulli wait minut centrifug minut rev min transfer supernat solut ml volumetr flask repeat centrifug ad ml acet acid residu collect solut chlorat volumetr flask fill mark acet acid reduct chlorat ml solut add zinc powder bring boil flask fit condens tube minut boil cool filter rins flask water filter combin filtrat rise determin chlorid titrat ml solut silver nitrat potentiomet titrat ml solut silver nitrat nb product bromin iodin deriv releas bromid iodid reduct titrat curv inflexion point case volum titrat solut chlorid differ penultim inflexion point calcul content chlorat sampl calcul formula chlorat clo volum millilitr silver nitrat solut titrat solut volum millilitr silver nitrat solut titrat millilitr solut molal silver nitrat standard solut mass sampl gram repeat chlorat content differ result determin carri parallel iso identif determin sodium iodat scope field applic method describ procedur identifi determin rins cosmet product sodium iodat identif principl sodium iodat separ halat thin layer chromatographi identifi oxid iodid form iodin reagent reagent analyt puriti refer solut aqueou solut potassium chlorat bromat iodat prepar freshli develop solvent ammonia solut aceton butanol potassium iodid aqueou solut starch solut hydrochlor acid apparatu readi cellulos thin layer chromatographi mm plate normal equip thin layer chromatographi procedur extract sampl water filter dilut ml deposit solut base line plate aliquot refer solut place plate tank develop ascend chromatographi quarter length plate solvent remov plate tank solvent evapor ambient temparatur nb hour sprai plate potassium iodid dry minut sprai starch dry minut final sprai hydrochlor evalu iodat present blue spot colour brown brown stand immedi rf approxim note bromat give reaction rf valu approxim chlorat minut rf valu determin definit sodium iodat content determin method express percentag mass sodium iodat principl sodium iodat dissolv water determin mean high perform liquid chromatographi seri revers phase column anion exchang column reagent reagent analyt puriti suitabl high perform liquid chromatographi hplc hydrochlor acid sodium sulphit aq sodium iodat stock solut prepar stock solut mg sodium iodat ml water potassium dihydrogenorthophosph disodium hydrogenorthophosph hplc mobil phase dissolv potassium dihydrogenorthophosph disodium hydrogenorthophosph litr water ph result solut univers indic paper ph apparatu ordinari laboratori apparatu circular filter paper diamet mm schleicher schuell equival high perform liquid chromatograph variabl wavelength detector column length mm intern diamet mm number connect seri column necleosil equival column vydac tm sb equival procedur sampl prepar fluid sampl shampoo weigh accur test portion approxim sampl ml glass stopper calibr tube measur flask fill mark water mix filter solut determin iodat solut mean hplc section solid sampl soap fine divid part sampl weigh accur test portion approxim ml glass stopper measur cylind fill ml water shake vigor minut centrifug filter filter paper mixtur stand night shake jellylik solut vigor filter filter paper determin iodat filtrat mean hplc section chromatographi flowrat ml min detector wavelength nm inject volum measur peak area calibr pipett ml sodium iodat stock solut ml volumetr flask fill mark mix solut obtain mg sodium iodat ml inject portion standard iodat solut liquid chromatograph obtain chromatogram determin peak area iodat plot curv relat peak area sodium iodat concentr calcul calcul sodium iodat content percentag mass formula sodium iodat vc mass gram test portion total volum sampl solut millilitr obtain concentr milligram millilitr sodium iodat obtain calibr curv repeat sodium iodat content differ result parallel determin carri sampl exce confirm principl acidifi solut cosmet product iodat io reduc iodid sulphit result solut investig mean hplc peak retent time retent time iodat disappear treatment sulphit origin peak attribut iodat procedur pipett ml portion sampl solut obtain section conic flask adjust ph solut lower hydrochlor acid univers indic paper add drop sodium sulphit solut mix inject portion solut liquid chromatograph compar chromatogram chromatogram obtain paragraph sampl sampl exce iso