Melting range á741ñ: between 114and 116.

Reaction— Its saturated solution is neutral to litmus.

Loss on drying á731ñ— Dry it over sulfuric acid for 2hours:it loses not more than 0.5%of its weight.

Residue on ignition(Reagent test): not more than 0.05%.

Residue on evaporation— Evaporate 50mLon a steam bath,and dry the residue at 105for 2hours:the residue weighs not more than 1mg (0.002%).

Chloride (Reagent test)— Five mLshows not more than 0.01mg of Cl (2ppm).

Sulfate (Reagent test,Method I)— Ten mLshows not more than 0.5mg of SO4(50ppm).

Heavy metals(Reagent test)— Evaporate 20mLon a steam bath to dryness.Add to the residue 2mLof the acid,dilute with water to 25mL,and add 10mLof hydrogen sulfide TS:any brown color produced is not darker than that of a control containing 0.04mg of added Pb and 2mLof the diluted acetic acid (2ppm).

Spectral purity— Measure in a 1-cm cell between 250nm and 280nm,with a suitable spectrophotometer,against air as the blank:its absorbance is not more than 0.01.

Melting range á741ñ: between 19and 20.

Refractive index á831ñ: about 1.534at 20.

Specific gravity á841ñ: about 1.03.

Assay— Inject an appropriate volume into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 230;the detector temperature is maintained at 300;and the column temperature is maintained at 130and programmed to rise 10per minute to 280.The area of the C9H11NOpeak is not less than 98.5%of the total peak area.

Melting range á741ñ: between 145and 151.

Assay— Not less than 98%of C5H8O2,a suitable gas chromatograph equipped with a flame-ionization detector being used and helium being used as the carrier gas.The following conditions have been found suitable:a 3-mm ×1.83-m stainless steel column containing 10%phase Gon support S1A;the injection port and detector temperatures are maintained at 250and 310,respectively;the column temperature is programmed to rise at 8per minute,from 50to 220.

Refractive index á831ñ: between 1.4505and 1.4525,at 20.

Melting range á741ñ— When previously dried at 110in a capillary tube for 1hour,it melts between 149and 152.

Reaction— Its 1in 10solution is neutral to litmus.

Residue on ignition(Reagent test): negligible,from 200mg.

Solubility in alcohol— Asolution of 500mg in 5mLof alcohol is complete and colorless.

Percent of acetyl (CH3CO)— Weigh accurately about 400mg,previously dried at 105for 3hours,and dissolve in 15mLof water in a glass-stoppered conical flask.Add 40.0mLof 0.1Nsodium hydroxide VS,and heat on a steam bath for 30minutes.Insert the stopper,allow to cool,add phenolphthalein TS,and titrate the excess alkali with 0.1Nsulfuric acid VS.Determine the exact normality of the 0.1Nsodium hydroxide by titrating 40.0mLafter it has been treated in the same manner as in the test.Each mLof 0.1Nsodium hydroxide is equivalent to 4.305mg of CH3CO.Between 23.2%and 24.2%is found.

Percent of chlorine(Cl)— Weigh accurately about 400mg,previously dried at 105for 3hours,and dissolve in 50mLof water in a glass-stoppered,125-mLflask.Add with agitation 30.0mLof 0.1Nsilver nitrate VS,then add 5mLof nitric acid and 5mLof nitrobenzene,shake,add 2mLof ferric ammonium sulfate TS,and titrate the excess silver nitrate with 0.1Nammonium thiocyanate VS:each mLof 0.1Nsilver nitrate is equivalent to 3.545mg of Cl.Between 19.3%and 19.8%of Cl is found.

Assay— Inject an appropriate specimen into a gas chromatograph (see Chromatography á621ñ),equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 150;the detector temperature is maintained at 300;and the column temperature is maintained at 50and programmed to rise 10per minute to 200.The area of the C3H4O2peak is not less than 99%of the total peak area.

Refractive index á831ñ: between 1.419and 1.423at 20.

Melting range á741ñ: between 270and 271.

Residue on ignition(Reagent test): negligible,from 100mg.

Water— Dry it at 105to constant weight:it loses not more than 10.0%of its weight.

Assay— Weigh accurately about 0.3g,and dissolve in 50mLof alcohol.Add 25mLof water,mix,and titrate with 0.5Nsodium hydroxide VSto a pHof 9.5.Perform a blank determination,and make any necessary correction.Each mLof 0.5Nsodium hydroxide is equivalent to 36.54mg of C6H10O4.Not less than 98%is found.

Melting range á741ñ: between 151and 155,but the range between beginning and end of melting does not exceed 2.

		Relative Proportions
Percent by Volume of C2H5OHat 15.56	Specific Gravity at 25	Alcohol,mL	Water,mL	Volume in mLof Alcohol, 94.9%v/v, Required for 100mL
70	0.884	38.6	15	73.7
80	0.857	45.5	9.5	84.3
90	0.827	51	3	94.8

[94.9(d/c)-0.8096]100,

Assay— Transfer about 20mg,accurately weighed,to a 200-mLvolumetric flask,dissolve in 1mLof water,dilute with an ice-cold solution of bovine serum albumin (1in 100)to volume,and mix.Use this solution as the Assay preparation.Dissolve 3.3g of potassium pyrophosphate,15mg of dithiothreitol,and 40mg of edetate disodium in 70mLof water,adjust with citric acid monohydrate solution (2.1in 10)to a pHof 9.0±0.1,dilute with water to 100mL,and mix to obtain a pH9.0buffer.Dissolve an accurately weighed quantity of b-nicotinamide adenine dinucleotide (b-NAD)in water to obtain a b-NADsolutionhaving a known concentration of about 20mg per mL.Pipet 0.1mLof the Assay preparationinto a 1-cm spectrophotometric cell.Pipet 0.1mLof water into a second 1-cm spectrophotometric cell to provide the reagent blank.Add 2.5mLof pH9.0buffer,0.2mLof b-NADsolution,and 0.1mLof pyrazole solution (0.68in 100)to each cell,and mix.Stopper the cells,and allow to stand for 2minutes at 25±1.Add 0.01mLof acetaldehyde solution (0.3in 100)to each cell,and mix.Stopper the cells,and determine the absorbance of the solution obtained from the Assay preparationat a wavelength of 340nm,using the solution obtained from the reagent blank as the reference.Calculate the change,DA,in absorbance per minute for the solution obtained from the Assay preparation,starting at the point when the absorbance and time relationship becomes linear.One enzyme activity unit is defined as the amount of enzyme that oxidizes 1µmol of acetaldehyde per minute when the test is conducted under the conditions described herein.Calculate the enzyme activity units in each mg of aldehyde dehydrogenase taken by the formula: in which DAis as defined above and Wis the weight,in g,of aldehyde dehydrogenase taken.

Arsenic— Place 750mg in a generator bottle (see Arsenic in Reagentsunder General Tests for Reagents),omitting the pledget of cotton.Add 10mLof water and 10mLof sodium hydroxide solution (3in 10),and allow the reaction to proceed for 30minutes:not more than a barely perceptible stain is produced on the mercuric bromide test paper.

pHof Slurry— The pHof a well-mixed slurry of 5g in 150mLof ammonia-free and carbon dioxide-free water,after 10minutes'standing,is between 3.5and 4.5.

Loss on ignition— Weigh accurately about 1g,and ignite,preferably in a muffle furnace at 800to 825,to constant weight:it loses not more than 5.0%of its weight.

Silica— Fuse 500mg with 10g of potassium bisulfate for 1hour in a platinum crucible,cool,and dissolve in hot water:not more than a small amount of insoluble matter remains.

Suitability for chromatographic adsorption— Dissolve 50mg of o-nitroaniline in benzene to make 50.0mL.Dilute 10mLof the resulting solution with benzene to 100.0mL,and mix (Solution A).

Nitrogen content(Reagent test)— Determine by the Kjeldahl method,using a test specimen previously dried at 105for 2hours:between 18.4%and 18.8%of Nis found,corresponding to not less than 98.5%of C2H5NO2.

Insoluble matter(Reagent test): not more than 1mg,from 10g (0.01%).

Residue on ignition(Reagent test): not more than 0.05%.

Chloride(Reagent test)— One g shows not more than 0.1mg of Cl (0.01%).

Sulfate(Reagent test,Method I)— Two g shows not more than 0.1mg of SO4(0.005%).

Heavy metals(Reagent test): 0.001%,5mLof 1Nhydrochloric acid being used to acidify the solution of the test specimen.

Iron á241ñ— One g,dissolved in 47mLof water containing 3mLof hydrochloric acid,shows not more than 0.01mg of Fe (0.001%).

Melting range á741ñ: between 108and 110.

Melting range á741ñ: between 49and 52.

Residue on ignition(Reagent test): not more than 2mg from 2g (0.1%).

Absorbance— A1in 200,000solution in methanol exhibits absorbance maxima at about 223nm,265nm,and 312nm.Its absorptivity (see Spectrophotometry and Light-Scattering á851ñ)at 265nm is about 64.0.

Melting range á741ñ: between 208and 212.

Ordinary impurities á466ñ—

Test solution: 1Nammonium hydroxide.

Standard solution: 1Nammonium hydroxide.

Eluant: 0.5Nsodium chloride.

Visualization: 1.

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with G2.The injection port temperature is maintained at 280;the column temperature is maintained at 180and programmed to rise 10per minute to 280and held there for 10minutes.The detector temperature is maintained at 300.The area of the main peak is not less than 97%of the total peak area.

Refractive index á831ñ: between 1.4978and 1.5010at 20.

Assay— Dissolve about 34mg,accurately weighed,in 50mLof glacial acetic acid.Titrate with 0.1Nperchloric acid VS,determining the end-point potentiometrically.Perform a blank determination and make any necessary corrections.Each mLof 0.1Nperchloric acid is equivalent to 13.61mg of CH6N4·H2CO3.Not less than 98.5%is found.

Melting point á741ñ: about 170,with decomposition.

Assay— Inject an appropriate specimen into a suitable gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with G2.The injection port temperature is maintained at 180;the column temperature is maintained at 80and programmed to rise 10per minute to 230and held there for 5minutes.The detector temperature is maintained at 300.The area of the main peak is not less than 95%of the total peak area.

Refractive index á831ñ: between 1.4840and 1.4860at 20.

Sensitiveness— Dissolve 100mg in 50mLof freshly prepared sodium bisulfite solution (1in 5),warming if necessary to effect solution,and filter.Add 1mLof the filtrate to a solution prepared by adding 2mLof dilute sulfuric acid (1in 6)and 1mLof Phosphate Reagent A(see Reagent test)to 20mLof a 1in 100dilution of Standard Phosphate Solution(see Reagent test):a distinct blue color develops within 5minutes.

Solubility in sodium carbonate solution— Dissolve 100mg in 3mLof sodium carbonate TS,and add 17mLof water:not more than a trace remains undissolved.

Residue on ignition(Reagent test)— To 1g add 0.5mLof sulfuric acid,and ignite at 800±25to constant weight:the residue weighs not more than 5mg (0.5%).

Sulfate(Reagent test,Method I)— Heat 500mg with a mixture of 25mLof water and 2drops of hydrochloric acid on a steam bath for 10minutes.Cool,dilute with water to 200mL,and filter:20mLof the filtrate shows not more than 0.25mg of SO4(0.5%).

Assay— Dissolve about 1.5g,accurately weighed,in about 400mLof water in a 500-mLvolumetric flask,dilute with water to volume,and mix.Transfer 25.0mLof this solution to an iodine flask,add 50.0mLof 0.1Nbromine VS,dilute with 50mLof water,add 5mLof hydrochloric acid,and immediately insert the stopper in the flask.Shake for 1minute,allow to stand for 2minutes,and add 5mLof potassium iodide TSthrough the slightly loosened stopper.Shake thoroughly,allow to stand for 5minutes,remove the stopper,and rinse it and the neck of the flask with 20mLof water,adding the rinsing to the flask.Titrate the liberated iodine with 0.1Nsodium thiosulfate VS,adding 3mLof starch TSas the endpoint is approached.From the volume of 0.1Nsodium thiosulfate used,calculate the volume,in mL,of 0.1Nbromine consumed by the test specimen.Each mLof 0.1Nbromine is equivalent to 1.819mg of C6H7NO:not less than 99.5%is found.

Melting range á741ñ: between 121and 123.

Loss on drying á731ñ— Dry it over calcium chloride for 4hours:the loss in weight is negligible.

Residue on ignition(Reagent test): negligible,from 2g.

Melting range á741ñ: between 187and 189.

Assay —Inject an appropriate specimen into a gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,helium being used as the carrier gas.The following conditions have been found suitable:a 0.25-mm ×30-m capillary column coated with a 1-µm layer of phase G2;the injection port temperature is maintained at 230;the detector temperature is maintained at 300;and the column temperature is maintained at 130and programmed to rise 10per minute to 280.The area of the C6H7NOpeak is not less than 99%of the total peak area.

Melting range á741ñ: between 174and 177.

Boiling range(Reagent test): between 184and 188.

Refractive index á831ñ: between 1.461and 1.463at 20.

Assay— When tested by thin-layer chromatography (see Chromatography á621ñ)with the use of plates coated with chromatographic silica gel mixture and a developing system consisting of a mixture of butanol,water,and acetic acid (60:25:15),examined under short-wavelength UVlight,a single spot is exhibited,with trace impurities.

Melting point á741ñ: 240,with decomposition.

Measuring range: 5to 70ppm.

Assay— Dissolve about 300mg,accurately weighed,in 50mLof a mixture of water and alcohol (25:25).Titrate with 0.1Nsodium hydroxide VS,determining the endpoint potentiometrically.Perform a blank determination and make any necessary correction.Each mLof 0.1Nsodium hydroxide is equivalent to 11.51mg of NH4HSO4.Not less than 98%is found.

Sensitiveness— Dissolve 50mg in 10mLof water.Add 0.2mLof the solution to 1mLof a solution of 10mg of choline chloride in 20mLof water,and shake gently:a distinct precipitate forms within 5to 10seconds.

Assay— Weigh accurately about 500mg,transfer to a suitable container,add 30mLof water and 2mLof dilute sulfuric acid (1in 4),swirl to dissolve,and pass sulfur dioxide gas through the solution until reduction is complete and the solution is bright blue in color.Boil gently while passing a stream of carbon dioxide through the solution to remove any excess sulfur dioxide,then cool,and titrate with 0.1Npotassium permanganate VS.Each mLof 0.1Npotassium permanganate consumed is equivalent to 11.7mg of NH4VO3.Not less than 98.0%is found.

Solubility in ammonium hydroxide— Dissolve 1g in a mixture of 3mLof ammonium hydroxide and 50mLof warm water:the solution is clear and colorless.

Carbonate— To 500mg add 1mLof water and 2mLof diluted hydrochloric acid:no effervescence is produced.

Chloride— Dissolve 250mg in 40mLof hot water,add 2mLof nitric acid,and allow to stand for 1hour.Filter,and to the filtrate add 0.5mLof silver nitrate TS:any turbidity produced does not exceed that of a blank containing 0.5mg of added Cl (0.2%).

Sulfate— Dissolve 500mg in 50mLof hot water,and add 2mLof diluted hydrochloric acid and 1.5g of hydroxylamine hydrochloride.Heat at 60for 3minutes,filter,cool,and add to the filtrate 2mLof barium chloride TS:no turbidity or precipitate is produced within 30minutes.

Boiling range(Reagent test,Method I): not less than 90%,between 137and 142.

Solubility in diluted alcohol— A1.0-mLportion dissolves in 20mLof diluted alcohol to form a clear solution.

Acidity— Add 5.0mLto 40mLof neutralized alcohol,and,if the pink color is discharged,titrate with 0.10Nsodium hydroxide:not more than 0.20mLis required to restore the pink color (about 0.02%as CH3COOH).

Water— A5-mLportion gives a clear solution with 5mLof carbon disulfide.

Boiling range(Reagent test): not less than 95%,between 100and 103.

Residue on evaporation— Evaporate 50mL(40g)on a steam bath,and dry at 105for 1hour:the residue weighs not more than 1.6mg (0.004%).

Acidsand esters— Dilute 20mLwith 20mLof alcohol,add 5.0mLof 0.1Nsodium hydroxide VS,and reflux gently for 10minutes.Cool,add 2drops of phenolphthalein TS,and titrate the excess sodium hydroxide with 0.1Nhydrochloric acid VS:not more than 0.75mLof the 0.10Nsodium hydroxide is consumed,correction being made for the amount consumed in a blank (0.06%as amyl acetate).

Aldehydes— Shake 5mLwith 5mLof potassium hydroxide solution (30in 100)in a glass-stoppered cylinder for 5minutes,and allow to separate:no color develops in either layer.

Moisture content of fully regeneratedand expanded resin— Transfer 10to 12mLof the resin (as received)to a flask,and convert it completely to the chloride form by stirring with 150mLof hydrochloric acid (5in 100)for not less than 30minutes.Decant the acid,and wash the resin in the same manner with distilled water until the wash water is neutral to litmus.

Total new volume capacity— Transfer 2.5to 3mLof the conditioned,undried (See Moisture content,above)resin to a 5-mLgraduated cylinder,and fill it with water.Remove any air bubbles from the resin bed with a stainless steel wire,and settle the resin to its minimum volume by tapping the graduated cylinder.Record the volume of the resin.

Wet screen analysis— The purpose of this test is to identify properly the mesh size of the resin.To obtain an accurate screen analysis requires special apparatus and technique.

Boiling temperature: 248.

Density: between 1.119and 1.123.

Refractive index á831ñ: between 1.5725and 1.5730at 20.

Assay— Inject an appropriate specimen (about 0.5µL)into a suitable gas chromatograph (see Chromatography á621ñ)equipped with a flame-ionization detector,nitrogen being used as the carrier gas.The following conditions have been found suitable:a 30-m capillary column is coated with phase G3;the injection port and detector are maintained at 140and 300,respectively;the column temperature is maintained at 70and programmed to rise 10per minute to 170.The area of the anisole peak is not less than 99%of the total peak area.

Refractive index á831ñ: 1.5160at 20.

Melting range á741ñ: between 215and 218.

Add the following:

Add the following:

Add the following:

Caution—Antimony pentachloride causes severe burns,and the vapor is hazardous.

Assay (SbCl5)— Weigh accurately a glass-stoppered,125-mLflask,quickly introduce about 0.3mLof the test specimen,and reweigh.Dissolve with 20mLof diluted hydrochloric acid (1in 5),and add 10mLof potassium iodide solution (1in 10)and 1mLof carbon disulfide.Titrate the liberated iodine with 0.1Nsodium thiosulfate VS.The brown color will gradually disappear from the solution,and the last traces of free iodine will be collected in the carbon disulfide,giving a pink color.When this pink color disappears the endpoint has been reached.Each mLof 0.1Nsodium thiosulfate is equivalent to 14.95mg of SbCl5:not less than 99.0%of SbCl5is found.

Sulfate(Reagent test,Method II)— Dissolve 4.3mL(10g)in the minimum volume of hydrochloric acid,dilute with water to 150mL,neutralize with ammonium hydroxide,and filter.To the filtrate add 2mLof hydrochloric acid:the solution,10mLof barium chloride TSbeing used,yields not more than 1.3mg of residue,correction being made for a complete blank test (0.005%).

Arsenic— Add 10mLof a recently prepared solution of 20g of stannous chloride in 30mLof hydrochloric acid to 100mg of specimen dissolved in 5mLof hydrochloric acid.Mix,transfer to a color-comparison tube,and allow to stand for 30minutes.Any color in the solution of the specimen should not be darker than that in a control containing 0.02mg of arsenic (As),which has been treated in the same manner as the test specimen,when viewed downward over a white surface (0.02%of As).

Iron á241ñ— To the residue from the test for Substances not precipitated by hydrogen sulfideadd 2mLof hydrochloric acid and 5drops of nitric acid,and evaporate on a steam bath to dryness.Take up the residue in 2mLof hydrochloric acid,and dilute with water to 47mL:the solution shows not more than 0.01mg of Fe (0.001%).

Other heavy metals(as Pb)— Dissolve the precipitate on the filter paper,from the test for Substances not precipitated by hydrogen sulfide,with 75mLof a solution containing 6g of sodium sulfide and 4g of sodium hydroxide dissolved in water and diluted with water to 100mL.Collect the filtrate in the original flask containing the remainder of the sulfide precipitate.Warm the solution to dissolve the soluble sulfides,and allow the insoluble sulfides to settle.Filter,wash thoroughly with hydrogen sulfide TS,and dissolve any precipitate remaining on the filter paper with 10mLof hot diluted hydrochloric acid.Dilute the filtrate with water to 50mL.Neutralize a 25-mLportion of this solution with 1Nsodium hydroxide,and add 1mLof 1Nacetic acid and 10mLof hydrogen sulfide TS.Any brown color should not exceed that produced by 0.05mg of lead ion in an equal volume of solution containing 1mLof 1Nacetic acid and 10mLof hydrogen sulfide TS(0.005%).

Substances not precipitated by hydrogen sulfide (as SO4)— Dissolve 0.90mL(2g)in 5mLof hydrochloric acid,and dilute with 95mLof water.Precipitate the antimony completely with hydrogen sulfide,allow the precipitate to settle,and filter,being careful not to transfer much of the precipitate to the filter paper.(Retain the precipitate.)To 50mLof the filtrate,add 0.5mLof sulfuric acid,evaporate in a tared porcelain crucible to dryness,and ignite at 800±25for 15minutes.(Retain the residue.)The weight of the ignited residue should not be more than 0.0010g greater than the weight obtained in a complete blank test (0.10%).

Change to read:

Assay— Dissolve about 200mg,previously dried at 105for 2hours and accurately weighed,in 20mLof dimethylformamide in a 100-mLconical flask.Add 4drops of thymol blue solution (1in 200in methanol),and titrate with 0.1Nlithium methoxide using a 10-mLburet,a magnetic stirrer,and a cover for the flask to protect against atmospheric carbon dioxide.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nlithium methoxide is equivalent to 21.02mg of C10H14N2O3.Between 98.5%and 101.0%of C10H14N2O3is found.

Melting range á741ñ: between 140and 143.

Melting range á741ñ: between 102and 104.

Water,Method Iá921ñ: not more than 0.5%.

Residue on ignition á281ñ: not more than 0.1%.

Melting temperature á741ñ: greater than 320.

Specific rotation á781ñ: between +31and +33,determined in a solution in diluted hydrochloric acid containing the equivalent of 5g (on the anhydrous basis,as determined by drying at 105for 5hours)in each 100mL.

Residue on ignition(Reagent test): not more than 0.1%.

Chloride(Reagent test)— One g shows not more than 0.03mg of Cl (0.003%).

Sulfate(Reagent test,Method I)— One g shows not more than 0.05mg of SO4(0.005%).

Heavy metals(Reagent test): 0.002%.

Nitrogen content,Method IIá461ñ: between 18.4%and 18.8%of Nis found.