1、Designation: E 50 00 (Reapproved 2005)Standard Practices forApparatus, Reagents, and Safety Considerations forChemical Analysis of Metals, Ores, and Related Materials1This standard is issued under the fixed designation E 50; the number immediately following the designation indicates the year of orig
2、inaladoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defens
3、e.1. Scope1.1 These practices cover laboratory apparatus and reagentsthat are required for the chemical analysis of metals, ores andrelated materials by standard methods of ASTM. Detaileddescriptions of recommended apparatus and detailed instruc-tions for the preparation of standard solutions and ce
4、rtainnonstandardized reagents are included. An identifying numberhas been assigned each apparatus (see Section 8) and reagent(see Section 25) for convenience of reference in the analyticalmethods. Included also are general recommendations on thepurity of reagents and protective measures for the use
5、ofhazardous reagents.1.2 The aim of these recommendations is to present descrip-tions of such apparatus and reagents as are common to severalASTM methods, and thus avoid needless repetition. No attempthas been made to provide a description of every apparatus andreagent prescribed inASTM methods for
6、the chemical analysisof metals. Other apparatus and reagents that are required willbe found listed or specified in the individual methods ofanalysis.1.3 These recommendations are intended to apply to theASTM methods of chemical analysis of metals when definitereference is made to these practices, as
7、 covered in Section 3.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of whoever uses this st
8、andard to consult andestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.Specific hazards are given in Section 7 and Note 2.NOTE 1The use of the verb “shall” (with its obligatory third personmeaning) in this standard has been conf
9、ined to those aspects of laboratorysafety where regulatory requirements are known to exist. Such regula-tions, however, are beyond the scope of these practices.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterE1 Specification for ASTM Liquid-in-Glass ThermometersE70 T
10、est Method for pH of Aqueous Solutions with theGlass ElectrodeE77 Test Method for Inspection and Verification of Ther-mometersE 100 Specification for ASTM HydrometersE 126 Test Method for Inspection and Verification of Hy-drometersE 128 Test Method for Maximum Pore Diameter and Per-meability of Rigi
11、d Porous Filters for Laboratory UseE 287 Specification for Laboratory Glass Graduated BuretsE 288 Specification for Laboratory Glass Volumetric FlasksE 438 Specification for Glasses in Laboratory ApparatusE 542 Practice for Calibration of Laboratory VolumetricApparatusE 694 Specification for Laborat
12、ory Glass Volumetric Appa-ratusE 969 Specification for Glass Volumetric (Transfer) PipetsE 1044 Specification for Glass Serological Pipets (GeneralPurpose and Kahn)E 1621 Guide for X-Ray Emission Spectrometric Analysis3. Significance and Use3.1 The inclusion of the following paragraph, or a suitable
13、equivalent, in any standard (preferably after the section onScope) is due notification that the apparatus and reagents1These practices are under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals, Ores, and Related Materials and are the directresponsibility of Subcommittee E01.
14、20 on Fundamental Practices and MeasurementTraceability.Current edition approved May 1, 2005. Published June 2005. Originallyapproved in 1943. Last previous edition approved in 2000 as E 50 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at se
15、rviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.required in that standard are subject to the recommen
16、dationsset forth in these practices.“Apparatus and ReagentsApparatus and reagents required for each de-termination are listed in separate sections preceding the procedure. Theapparatus, standard solutions, and certain other reagents used in morethan one procedure are referred to by number and shall
17、conform to therequirements prescribed in ASTM Practices E 50, for Apparatus, Reagents,and Safety Considerations for Chemical Analysis of Metals, Ores, and Re-lated Materials.”3.2 It is assumed that the users of these practices will betrained analysts capable of performing common laboratoryprocedures
18、 skillfully and safely. It is expected that work will beperformed in a properly-equipped laboratory.4. Purity of Water and Reagents4.1 WaterUnless otherwise indicated, references to waterare understood to mean reagent water of Type II grade, asdefined by Specification D 1193.4.2 ReagentsUnless other
19、wise indicated, it is intendedthat all reagents conform to the specifications of the Committeeon Analytical Reagents of the American Chemical Societywhen such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to per
20、mit its use without lessening theaccuracy of the determination. In addition to this, it is desirablein many cases for the analyst to ensure the accuracy of hisresults by running blanks or checking against a comparablesample of known composition.5. Reagents5.1 Concentrated Acids, Ammonium Hydroxide,
21、and Hydro-gen PeroxideWhen acids, ammonium hydroxide, and hydro-gen peroxide are specified by name or chemical formula only,it is understood that concentrated reagents of the specificgravities or concentrations shown in Table 1 are intended. Thespecific gravities or concentrations of all other conce
22、ntratedacids are stated wherever they are specified.5.2 Diluted Acids and Ammonium HydroxideConcentrations of diluted acids and ammonium hydroxide,except when standardized, are specified as a ratio stating thenumber of volumes of the concentrated reagent to be dilutedwith a given number of volumes o
23、f water, as in the followingexample: HCl (5 + 95) means 5 volumes of concentrated HCl(sp gr 1.19) diluted with 95 volumes of water.5.3 Standard SolutionsConcentrations of standard solu-tions are stated as molarities or normalities, expressed deci-mally; or the equivalent of 1 mL of solution in terms
24、 of grams,milligrams, or micrograms of a given element expressed as “1mL = x.xxg, mg, or g of.”5.4 Nonstandardized SolutionsConcentrations of non-standardized solutions prepared by dissolving a given weightof the solid reagent in a solvent are specified in grams of thesalt as weighed out per litre o
25、f solution, and it is understood3“Reagent Chemicals,American Chemical Society Specifications,”Am. Chemi-cal Soc., Washington, DC. For suggestions on the testing of reagents not listed bytheAmerican Chemical Society, see “Reagent Chemicals and Standards,” by JosephRosin, D. Van Nostrand Co., Inc., Ne
26、w York, NY, and the “United StatesPharmacopeia.” United States Pharmacopeial Convention, Rockville, MD 20852.TABLE 1 Concentration of Acids, Ammonium Hydroxide, and Hydrogen PeroxideName FormulaSpecificGravity,ApproximateReagent, Weight %Nominal Min MaxAcetic acid CH3COOH 1.05 . 99.5 .Formic acid HC
27、OOH 1.20 . 88.0 .Hydrobromic acid HBr 1.49 48 47.0 49.0Hydrochloric acid HCl 1.19 . 35.0 38.0Hydrofluoric acid HF 1.15 . 48.0 51.0Nitric acid HNO31.42 . 69.0 71.0Perchloric acid HClO41.67 . 70.0 72.0Phosphoric acid H3PO41.69 . 85.0 .Sulfuric acid H2SO41.84 . 95.0 98.0Sulfurous acid H2SO31.03 . 6.0(S
28、O2) .Ammonium hydroxide NH4OH 0.90 . 27.0(NH3) 30.0 (NH3)Hydrogen peroxide H2O21.10 30 28.0 .TABLE 2 Physical Properties of Plastic LabwareAPlasticBTemperature Limit, C Specific GravityBrittlenessTemperature, CWater Absorption, % Flexibility TransparencyCPE 80 0.92 100 0.01 excellent translucentLPE
29、120 0.95 196 0.01 rigid translucentPA 130 0.90 40 0.02 slight translucentPP 135 0.90 0 0.02 rigid translucentPMP 175 0.83 20 0.01 rigid clearFEP 205 2.15 270 0.01 excellent translucentTFE 315 2.2 265 0.01 excellent translucentPC 135 1.20 135 0.35 rigid clearSA 95 1.07 25 0.23 rigid clearETFE 180 1.7
30、0 100 0.1 moderate translucentAFrom the publications of the Nalgene Labware Div., Nalge Sybron Corp.BCPE, conventional (low density) polyethylene; LPE, linear (high density) polyethylene; PA, polyallomer (ethylene propylene copolymer); PP, polypropylene; PMP,polymethylpentene; FEP, fluorinated ethyl
31、ene propylene; TFE, fluorinated ethylene; PC, polycarbonate; SA, styrene-acrylonitrile; ETFE, ethylene-tetrafluoroethylenecopolymer.E 50 00 (2005)2that water is the solvent unless otherwise specified. Forexample, to prepare barium chloride solution (100 g/L) dis-solve 100 g of barium chloride (BaCl2
32、2H2O) in water anddilute to 1 L. In the case of certain reagents, the concentrationmay be specified as a weight percent. For example, H2O2(3 %)means a solution containing3gofH2O2per 100 g of solution.Other nonstandardized solutions may be specified by nameonly and the designation of the concentratio
33、n of such solutionswill be governed by the instructions for their preparation.6. Laboratory Ware (1,2)4,56.1 GlasswareUnless otherwise stated all analytical meth-ods are carried out in borosilicate glassware.6.1.1 TolerancesAll glass apparatus and vessels used inanalytical work must be carefully sel
34、ected and calibrated tomeet the particular requirements for each operation. Standardvolumetric flasks, burets, and pipets must be of Class A or Bwithin the tolerances established by the National Institute ofStandards and Technology and ASTM.56.1.2 TypesGlasses are available which include coloredglas
35、s for the protection of solutions affected by light, alkali-resistant glass, and high-silica glass having exceptional resis-tance to thermal shock. Standard-taper, interchangeable,ground-glass joints are very useful in analytical work.6.2 Plastic Labware:6.2.1 TolerancesAll plastic apparatus and ves
36、sels used inanalytical work must be calibrated to meet the particularrequirements for each operation. Standard volumetric flasks,burets, and pipets must be of precision grade within thetolerances established by the National Institute of Standardsand Technology for the corresponding types of glasswar
37、e (see6.2.4).6.2.2 Physical PropertiesThere are a number of physicalproperties which influence the usefulness of plastic labware(Table 2).6.2.3 CompatibilityMany reagents can affect the strength,flexibility, surface appearance, color, dimensions, or weight ofplastics. The two basic modes of interact
38、ion that can causethese changes are described in 6.2.3.1-6.2.3.4.6.2.3.1 ChemicalThe analytical reagents can react withthe polymer chain by oxidation, by attack on functional groupsin or on the polymer molecule, or by depolymerization with aresultant deterioration in physical properties.66.2.3.2 Phy
39、sicalAbsorption of solvents in the plastic canresult in softening, swelling, and permeation of the solventthrough the plastic. No room temperature solvents are knownfor the polyolefins, however, it is better not to use them to storereagents. Reagents such as NH3,Br2,H2S, and nitrogen oxidesmay be ab
40、sorbed from reagent solutions by the plastic andbecome a source of error by subsequent release when the vesselis used for a different analysis.7Atmospheric contaminantsmay diffuse through the plastic and spoil contained reagents orsamples. Other polymer types may dissolve in some solvents.Plastic la
41、bware may crack from interaction of a “stresscracking agent” (present, possibly in the solution to be ana-lyzed) with molded-in stresses. This is, however, a long-timephenomenon and is normally not a factor in analytical workbecause contact times usually are limited and the labware iswashed regularl
42、y.6.2.3.3 Some plastics may contain small concentrations ofmetals used as catalysts during manufacture. Such metals maydissolve in the analytical reagent system and cause interfer-ence, particularly when small amounts of metals are to bedetermined.6.2.3.4 A general indication of the effect of indivi
43、dualreagents can often be obtained from manufacturers publica-tions. It is important, of course, to consider that exposure time,temperature, concentration, and other reagents in the systemmay alter the effects of a given reagent on a given plastic.Because of these factors, the plastic labware must b
44、e thor-oughly tested under the conditions of the method.6The type ofplastic labware (see footnote B of Table 2) will be foundspecified in the method as well as any special precautions forits use.6.2.4 PrecautionsMost plastic labware must not be usedwith strong oxidants at elevated temperatures; or e
45、xposed tolocalized or general temperature above the limits in Table 2.8With proper precaution polytetrafluoroethylene labware maybe used with strong oxidizing agents at elevated temperatures(see Table 2). For the best performance new volumetric wareshould be rinsed with a mild detergent according to
46、 thedirections of the manufacturer before using. Plastic volumetricware shrinks slightly as it ages; therefore, it must be recali-brated periodically. Interior surfaces of volumetric ware shouldnot be cleaned by abrasive action.7. Hazards (3-8)7.1 General RequirementsNearly all procedures carriedout
47、 in the chemical laboratory are potentially hazardous. Eachof the procedures used in these methods of chemical analysis ofmetals has been safely performed many times in a number oflaboratories. Specific warnings are given in the methods whenunusually hazardous steps are required, but the analyst mus
48、trely on his own knowledge and skill to avoid the commonhazards. The following general concepts have been developedthrough many years of industrial laboratory operations:7.1.1 Each person who works in a chemical laboratoryshould protect himself and others from harm. Each individualshould adopt an at
49、titude of anticipating potential hazards andplanning means for reducing the associated risk to a tolerablelevel. This involves the proper implementation of approvedprocedures, personal protective equipment, and risk manage-ment policy.4The boldface numbers in parentheses refer to the list of references at the end ofthese practices.5For further information the following ASTM Standards may be consulted:Volumetric Labware: Specifications E 287, E 288, E 438, Practice E 542, Specifi-cations E 694, E 969, and E 1044. Thermometers: Specification E 1, and Te
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