1、Designation: D3505 121Standard Test Method forDensity or Relative Density of Pure Liquid Chemicals1This standard is issued under the fixed designation D3505; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1NOTEEditorial changes were made in Section 11.4 and Section 1
3、2 in April 2013.1. Scope*1.1 This test method describes a simplified procedure for themeasurement of density or relative density of pure liquidchemicals for which accurate temperature expansion functionsare known. It is restricted to liquids having vapor pressures notexceeding 79 993 Pascal (0.800 b
4、ar, 600 mm Hg (0.789 atm)at the equilibration temperature, and having viscosities notexceeding 15 cSt at 20C.1.2 Means are provided for reporting results in the follow-ing units:Density g/cm3at 20CDensity g/mL at 20CRelative density 20C/4CRelative density 15.56C/15.56CNOTE 1This test method is based
5、 on the old definition of 1 L =1.000028 dm3(1 mL= 1.000028 cm3). In 1964 the General Conference onWeights and Measures withdrew this definition of the litre and declaredthat the word “litre” was a special name for the cubic decimetre, thusmaking 1 mL = 1 cm3exactly.NOTE 2An alternative method for de
6、termining relative density of pureliquid chemicals is Test Method D4052.1.3 The following applies to all specified limits in this testmethod: for purposes of determining conformance with thistest method, an observed value or a calculated value shall berounded off “to the nearest unit” in the last ri
7、ght-hand digitused in expressing the specification limit, in accordance withthe rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafe
8、ty concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific hazardstatements are given in 7.1.2. Referenced Documents2.1 ASTM
9、 Standards:2D1193 Specification for Reagent WaterD1555 Test Method for Calculation of Volume and Weightof Industrial Aromatic Hydrocarbons and CyclohexaneD3437 Practice for Sampling and Handling Liquid CyclicProductsD4052 Test Method for Density, Relative Density, and APIGravity of Liquids by Digita
10、l Density MeterD6809 Guide for Quality Control and Quality AssuranceProcedures for Aromatic Hydrocarbons and Related Ma-terialsE1 Specification for ASTM Liquid-in-Glass ThermometersE12 Terminology Relating to Density and Specific Gravityof Solids, Liquids, and Gases (Withdrawn 1996)3E29 Practice for
11、 Using Significant Digits in Test Data toDetermine Conformance with Specifications2.2 Other Document:OSHA Regulations, 29 CFR paragraphs 1910.1000 and1910.120043. Terminology3.1 Definitions:3.1.1 density, nthe mass of material per unit volume at agiven temperature called the “reference temperature.”
12、 Weightcorrected to a standard acceleration of gravity and corrected forthe buoyant effect of air is used to measure mass. This methodspecifies the use of a beam balance to determine weight so that1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related C
13、hemicals and is the direct responsibility ofSubcommittee D16.04 on Instrumental Analysis.Current edition approved March 1, 2012. Published May 2012. Originallyapproved in 1976. Last previous edition approved in 2006 as D3505 96 (2006).DOI: 10.1520/D3505-12E01.2For referenced ASTM standards, visit th
14、e ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from U
15、.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1
16、9428-2959. United States1no correction for variation in acceleration of gravity is neces-sary. When a torsion or spring balance is used, such correctionmust be applied.3.1.2 relative density, nthe ratio of the density of thematerial at reference temperature “t” to the density of purewater, in consis
17、tent units, at reference temperature t2.Itiscommon practice to use reference temperature t1equal to t2.3.1.2.1 Since the mass of water at 4C is very close to 1g/mL or 1 g/cm3, it is common practice to set the referencetemperature t2for water at 4C. When this is done and thedensity of the material is
18、 given in grams per millilitre, or gramsper cubic centimetre, the value of density is very nearlyidentical to the value for relative density. Thus, density at 20Cin g/cm3or g/mL, is nearly identical with relative density20C/4C.3.2 The definitions included in Terminology E12 are appli-cable to this t
19、est method.4. Summary of Test MethodNOTE 3See Appendix X1 for details on the method and derivation offormulas.4.1 For materials listed in Table 1 the sample is drawn intoa weighed and calibrated bicapillary pycnometer. The fillerpycnometer is allowed to come to equilibrium at any conve-nient tempera
20、ture between 10 and 30C. The equilibriumtemperature is measured to the nearest 0.02C. The weight isdetermined using a beam balance. The density, relative density,or commercial density at the desired reference temperature isthen calculated from the sample weight, a calibration factorproportional to a
21、n equal volume of water, and a multiplierwhich corrects for the buoyancy of air and the change involume of the pycnometer and the sample due to deviationfrom the chosen reference temperature.4.2 For liquids not listed in Table 1, the sample is equili-brated at the desired reference temperature, usua
22、lly 20C or15.56C, the density, relative density, or commercial density isthen calculated from the sample weight, a calibration factorproportional to an equal volume of water and a term whichcorrects for the buoyancy of air. In the case of volatile liquidssuch as pentane, the time between reading of
23、volume at theequilibrium temperature and weighing must not be prolonged,otherwise weight loss through evaporation may result inerrors.55. Significance and Use5.1 This test method is suitable for setting specification, foruse as an internal quality control tool, and for use in develop-ment or researc
24、h work on industrial aromatic hydrocarbons andrelated materials. In addition to the pure liquid chemicals forwhich expansion functions are known, it may also be used forliquids for which temperature expansion data are not available,or for impure liquid chemicals if certain limitations areobserved. I
25、nformation derived from this test can be used todescribe the relationship between weight and volume.6. Apparatus6.1 Pycnometer, 9 to 10-mL capacity, conforming to thedimensions given in Fig. 1, constructed of borosilicate glass,and having a total weight not exceeding 30 g.6.2 Bath, having a depth of
26、 at least 300 mm, capable ofbeing maintained constant to 60.02C at any convenienttemperature between 10C and 30C. Provide a support for thepycnometer (see Fig. 2) constructed of any suitable noncorro-sive metal.NOTE 4If the laboratory air temperature does not vary more than0.02C during temperature e
27、quilibration a special bath is not needed.6.3 Bath Thermometer, an ASTM Precision Thermometer,having a range from 8 to +32C and conforming to therequirements for Thermometer 63C as prescribed in Specifi-cation E1.7. Hazards7.1 Consult current OSHA regulations, suppliers MaterialSafety Data Sheets, a
28、nd local regulations, for all materials usedin this test method.8. Sampling8.1 Sample the material in accordance with Practice D3437.9. Preparation of Apparatus9.1 Acid Cleaning, for use when the pycnometer is to becalibrated or when liquid fails to drain cleanly from the wallsof the pycnometer or i
29、ts capillary. Thoroughly clean with hotchromic acid solution and rinse well with reagent waterconforming to Type III of Specification D1193. Other suitablecleaning procedures may be used. Dry at 105 to 110C for atleast 1 h, preferably with a slow current of filtered air passingthrough the pycnometer
30、.9.2 Solvent Cleaning, for use between determinations. Rinsewith toluene and then with anhydrous acetone, drying with afiltered stream of dry air.10. Calibration of Apparatus10.1 Using the procedure described in Section 11, determinethe weight of freshly boiled reagent water conforming to TypeIII of
31、 Specification D1193 held by the pycnometer with thewater level at each of three different scale points on thegraduated arms. Two of these water levels must be at oppositeends of the scale. Make all weighings on the same day, usingthe same balance and weights.10.2 Calculate the volume, VTp, at each
32、scale point testedby means of the following equation; carry all calculations in 6non-zero digits and round to 4 decimal places:5For a more complete discussion on the use of this design pycnometer, seeLipken, Davidson, Harvey and Kurtz, Industrial Engineering Chemistry, AnalyticalEdition; Vol 16, 194
33、4, p. 55.D3505 1212TABLE 1 PART I 20C Reference Temperature Multiplier, F20, for use in Computing Density, 12.1D3505 1213TABLE 1 PART I ContinuedD3505 1214TABLE 1 PART II 60F Reference Temperature Multiplier, F15.56, for use in Computing Density, 12.1D3505 1215TABLE 1 PART II ContinuedD3505 1216Pycn
34、ometer capacity, VTp, mL 5 A 3 Ww/dtw!1BT 2 t! (1)where:A = air buoyancy coefficient, a constant for the tempera-ture range involved = 1.001064VTp= volume of pycnometer at reference temperature, TWw= weight of water in air, contained in the pycnometer, gdtw= density of water at t (see Table 2)t = te
35、st temperature, CT = reference temperature, 20C or 15.56C, andB = volumetric coefficient of expansion of 9.5 mL of aborosilicate glass pycnometer, 9.26276 105mL/C.10.3 Prepare a calibration curve by plotting apparentvolume, VA, that is, the sum of the scale readings on the twoarms of the pycnometer
36、against the corresponding calculatedvolume, VTp. If a straight line cannot be drawn through thethree points, discard the data and determine three additionalpoints so that a straight calibration line can be drawn such thatno data point lies more than 0.0002-mL units from the line. Ifneither set of da
37、ta meets the condition, the diameters of thegraduated capillary arms are not sufficiently uniform, and thepycnometer should be discarded.10.4 From the curve obtained, prepare a table of apparentvolume, VA, (sum of scale readings of both arms), as apparentvolume against corresponding calculated volum
38、es, VTp,inincrements of 0.0001 mL. Label this table with the referencetemperature to which it applies.11. Procedure11.1 Weigh the clean, dry pycnometer to 0.1 mg and recordthe weight.11.2 With the sample at approximately the test temperature,fill the pycnometer by holding it in an upright position a
39、ndplacing the hooked tip in the sample; the liquid will then bedrawn over the bend in the capillary by surface tension. Allowthe pycnometer to fill by siphoning (about 1 min) and break thesiphon when the liquid level in the bulb arm of the pycnometerreaches the lowest graduation mark.11.3 Thoroughly
40、 dry the wet tip. Wipe the body of thepycnometer with a chemically clean, lint-free cloth slightlydamp with water (Note 4) and weigh the filled pycnometer tothe nearest 0.1 mg.NOTE 5In atmospheres below 60 % relative humidity, drying thepycnometer by rubbing with a dry cotton cloth will induce stati
41、c chargesequivalent to a loss of about 1 mg or more in the weight of thepycnometer. This charge may not be completely dissipated in less than12h, and can be detected by touching the pycnometer to the wire hook in thebalance and then drawing it away slowly. If the pycnometer exhibits anattraction for
42、 the wire hook, it may be considered to have a static charge.11.4 Place the pycnometer in the holder in a constant-temperature bath held at any convenient temperature betweenNOTE 1The graduation lines shall extend around the entire circum-ference of the pycnometer at the integral numbers 0, 1, 2 cm,
43、 etc., half wayaround at the half divisions 0.5, 1.5, etc., and shorter lines for theintermediate subdivisions.FIG. 1 PycnometerNOTE 1All dimensions are in Meters.FIG. 2 Pycnometer HolderD3505 121710 and 30C within 60.02C; for materials not listed in Table1, hold the bath exactly at the desired refe
44、rence temperature,usually 15.56C or 20C. When the liquid level has reachedtemperature equilibrium (usually in about 10 min) and whilestill in the bath, read the scale to the nearest 0.2 small divisionat the liquid level in each arm.12. Calculation12.1 Table 1 MaterialsCompute the density or relative
45、density, or both, by means of the following equations:Density, g/mL at 15.56C 5 Ws/V15.56p! 3F15.5610.00121 (2)Density, g/mL at 20C 5WsV20p3F2010.00121 (3)Density, g/cm3at 20C 5FWsV20pF2010.00121G0.99997 (4)Relative density 15.56/15.56C 5 Ws/V15.56p! 3F15.5610.00121# 1.00096 (5)where:Ws= observed we
46、ight of sample, corrected forvariation of weights, g,V20p,V15.56p= calculated volume, VTp, of sample at 20C or15.56C, millilitres, obtained from the pyc-nometer calibration table (Note 5),F20,F15.56= constants taken from Table 1. Correspondingto the test temperature, tCNOTE 6For frequently examined
47、products it should prove convenientto combine Table 1 with the calibration table described in 10.2.12.2 General MethodCompute the density or relativedensity, or both, by means of the following equations:Density, g/mL at 20C 5WsV20p1C (6)Density, g/cm3at 20C 5FWsV20p1CG0.99997 (7)Relative density 15.
48、56/15.56C 5 Ws/V15.56p1C# 1.00096 (8)where:Ws= observed weight of sample, corrected forvariation of weights, g,V20p,V15.56p= calculated volume, VTp, of sample at 20C or15.56C obtained from the pycnometer cali-bration table, andC = air buoyancy correction factor from Table 3.13. Precision and Bias613
49、.1 The following data should be used for judging theacceptability of results (95 % probability) for the materials ofTable 1:13.1.1 RepeatabilityDuplicate results by the same opera-tor should not be considered suspect unless they differ by morethan the following amounts:0.0002 g/mL13.1.2 ReproducibilityThe results submitted by one labo-ratory should not be considered suspect unless it differs fromthat of another laboratory by more than the following amounts:0.0003 g/mL14. Quality Guidelines14.1
