additive-258-m1

MAGNESIUMCHLORIDEPreparedatthe27thJECFA(1983),publishedinFNP28(1983)andinFNP52(1992).Metalsandarsenicspecificationsrevisedatthe63rdJECFA(2004).AnADI'Notlimited'wasestablishedatthe23rdJECFA(1979).SYNONYMSINSNo.511DEFINITIONChemicalnamesMagnesiumchloridehexahydrateC.A.S.number7786-30-3ChemicalformulaMgCl2·6H2OFormulaweight203.30AssayNotlessthan99.0%andnotmorethan105.0%DESCRIPTIONColourless,odourlessflakes,granules,lumpsorcrystals;itisverydeliquescentFUNCTIONALUSESFirmingagent,colourretentionagentCHARACTERISTICSIDENTIFICATIONSolubility(Vol.4)Verysolubleinwater;freelysolubleinethanolTestforchloride(Vol.4)PassestestTestformagnesium(Vol.4)PassestestPURITYAmmoniumNotmorethan50mg/kgDissolve1gofthesamplein90mlofwater,andslowlyadd10mlofafreshlyboiledandcooledsolutionofsodiumhydroxide(1in10soln).Allowtosettle,thendecant20mlofthesupernatantliquidintoacolourcomparisontube,diluteto50mlwithwater,andadd2mlofNessler'sTS.Anycolourdoesnotexceedthatproducedby10µgofammonium(NH4)ionin48mlofwaterand2mlofthesodiumhydroxidesolution.Lead(Vol.4)Notmorethan2mg/kgDetermineusinganatomicabsorptiontechniqueappropriatetothespecifiedlevel.TheselectionofsamplesizeandmethodofsamplepreparationmaybebasedontheprinciplesofthemethoddescribedinVolume4,“InstrumentalMethods.”METHODOFASSAYDissolveabout450mgofthesample,accuratelyweighed,in25mlofwater,add5mlofammonia/ammoniumchloridebufferTSand0.1mloferiochromeblackTSandtitratewith0.05Mdisodiumethylenediaminetetraacetateuntilthesolutionisblueincolour.Eachmlof0.05Mdisodiumethylenediaminetetra-acetateisequivalentto10.16mgofMgCl2·6H2O.