Designation:E169−04(Reapproved2014)StandardPracticesforGeneralTechniquesofUltraviolet-VisibleQuantitativeAnalysis1ThisstandardisissuedunderthefixeddesignationE169;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thesepracticesareintendedtoprovidegeneralinfor-mationonthetechniquesmostoftenusedinultravioletandvisiblequantitativeanalysis.Thepurposeistorenderunnec-essarytherepetitionofthesedescriptionsoftechniquesinindividualmethodsforquantitativeanalysis.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2E131TerminologyRelatingtoMolecularSpectroscopyE168PracticesforGeneralTechniquesofInfraredQuanti-tativeAnalysis(Withdrawn2015)3E275PracticeforDescribingandMeasuringPerformanceofUltravioletandVisibleSpectrophotometersE925PracticeforMonitoringtheCalibrationofUltraviolet-VisibleSpectrophotometerswhoseSpectralBandwidthdoesnotExceed2nmE958PracticeforEstimationoftheSpectralBandwidthofUltraviolet-VisibleSpectrophotometers3.SummaryofPractice3.1Quantitativeultravioletandvisibleanalysesarebasedupontheabsorptionlaw,knownasBeer’slaw.TheunitsofthislawaredefinedinTerminologyE131.Beer’slaw(Note1)holdsatasinglewavelengthandwhenappliedtoasinglecomponentsampleitmaybeexpressedinthefollowingform(seeSection10):A5abc(1)Whenappliedtoamixtureofnnon-interactingcomponents,itmaybeexpressedasfollows:A5a1bc11a2bc21….1anbcn(2)NOTE1—DetaileddiscussionoftheoriginandvalidityofBeer’slawmaybefoundinthebooksandarticleslistedinthebibliographyattheendofthes...
