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  • Reagent ChemicalsNinth Edition

    ACS SpecificationsOfficial from January 1, 20002000 American Chemical Society

    Reagent: Hydrogen Peroxide

    Hydrogen PeroxideH2O2 Formula Wt 34.01

    CAS Number 7722841NOTE. This reagent should be stored in a cool place in containerswith a vent in the stopper. The assay requirement applies to mate-rial stored properly for a reasonable time.

    REQUIREMENTSAssay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.032.0% H2O2

    MAXIMUM ALLOWABLEColor (APHA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Residue after evaporation . . . . . . . . . . . . . . . . . . . . . . . . 0.002%Titrable acid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.0006 meq/gChloride (Cl). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 ppmNitrate (NO3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 ppmPhosphate (PO4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 ppmSulfate (SO4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 ppmAmmonium (NH4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 ppmHeavy metals (as Pb) . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 ppmIron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 ppm

    TESTS

    ASSAY. (By titration of the reductive capacity). Weigh accurately about 1 mL in atared 100-mL volumetric flask, dilute to volume with water, and mix thoroughly.To 20.0 mL of this solution add 20 mL of dilute sulfuric acid (1 + 15) and titratewith 0.1 N potassium permanganate. One milliliter of 0.1 N potassium perman-ganate corresponds to 0.01700 g of H2O2.

    COLOR (APHA). (Page 19).

    RESIDUE AFTER EVAPORATION. (Page 16). Evaporate 50 g (45 mL) to dry-ness in a tared porcelain or silica dish on a hot plate (100 C) and dry the residueat 105 C for 30 min.

    TITRABLE ACID. Dilute 10 g (9 mL) with 90 mL of carbon dioxide-free water.Add 0.15 mL of methyl red indicator solution and titrate with 0.01 N sodiumhydroxide. The volume of sodium hydroxide solution consumed should not bemore than 0.6 mL greater than the volume required for a blank test on 90 mL ofthe water used for dilution.

    CHLORIDE, NITRATE, PHOSPHATE, AND SULFATE. (By ion chromatogra-phy, page 74). Obtain three 100-mL beakers (blank, test, standard) and add 10mL water and 2.0 mg of sodium carbonate to each. Add 10.5 g (9.45 mL) of thesample to the standard and test. To the standard, add 0.02 mg each of chloride,nitrate, and phosphate ions and 0.05 mg of sulfate ion. To the blank, add 0.5 g(0.45 mL) of the sample. Evaporate each to dryness on a steam bath or low-tem-perature hot plate. Dissolve the residues in a little water and dilute each to 25 mL.Analyze 50-mL or 100-mL aliquots by ion chromatography and measure the vari-ous peaks. The differences between the sample and the blank should not begreater than the corresponding differences between the standard and the sample.

  • Reagent ChemicalsNinth Edition

    ACS SpecificationsOfficial from January 1, 20002000 American Chemical Society

    Reagent: Hydrogen Peroxide

    AMMONIUM. Add 0.1 mL of sulfuric acid to 2 g (1.8 mL) of the sample andevaporate on a hot plate (100 C). Dissolve the residue in 45 mL of water andadd 3 mL of 10% sodium hydroxide reagent solution and 2 mL of Nessler reagent.Any color should not exceed that produced by 0.01 mg of ammonium ion (NH4)in an equal volume of solution containing the quantities of reagents used in thetest.

    HEAVY METALS. (Page 28, Method 1). To 20 g (18 mL) in a 100-mL beaker addabout 10 mg of sodium chloride and evaporate to dryness on a hot plate (100C). Dissolve the residue in about 20 mL of water and dilute with water to 25 mL.

    IRON. (Page 30, Method 1). To 20 g (18 mL) in a 100-mL beaker, add about 10mg of sodium chloride, and evaporate to dryness on a hot plate (100 C). Dis-solve in 2 mL of hydrochloric acid, dilute with water to 50 mL, and use the solu-tion without further acidification.


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