Packaging and storage
Preserve in tight, single-dose containers, preferably of Type I glass, and store at controlled room temperature. The container may contain an inert gas in the headspace.
Identification
A:
Mix 5 drops in a small beaker with 1 mL of potassium permanganate solution (1 in 100) and 5 drops of 2 N sulfuric acid, and cover the beaker immediately with a filter paper moistened with a solution recently prepared by dissolving 0.1 g of sodium nitroferricyanide and 0.25 g of piperazine in 5 mL of water: an intense blue color is produced on the filter paper, the color becoming paler after a few minutes.
B:
To 5 mL of a solution (1 in 10) add 1 mL of 1.0 N sodium hydroxide, then slowly (over a period of 3 minutes) add 2 mL of 0.1 N iodine: the odor of iodoform develops, and a yellow precipitate is formed within 30 minutes.
Specific gravity 841:
not more than 0.8035 at 15.56
, indicating not less than 96.8%, by weight, of C
2H
5OH.
Acidity
To 50 mL, in a glass-stoppered flask, add 50 mL of recently boiled water. Add
phenolphthalein TS, and titrate with 0.020 N sodium hydroxide to a pink color that persists for 30 seconds: not more than 10.0 mL of 0.020 N sodium hydroxide is required for neutralization.
Limit of nonvolatile residue
Evaporate 40 mL in a tared dish on a water bath, and dry at 105
for 1 hour: the weight of the residue does not exceed 1 mg.
Water-insoluble substances
Dilute it with an equal volume of water: the mixture is clear and remains clear for 30 minutes after cooling to 10
.
Aldehydes and other foreign organic substances
Place 20 mL in a glass-stoppered cylinder that has been thoroughly cleaned with hydrochloric acid, then rinsed with water and finally with the dehydrated alcohol to be tested. Cool the contents to approximately 15
, and add, by means of a carefully cleaned pipet, 0.10 mL of 0.10 N potassium permanganate, noting accurately the time of addition. Mix at once by inverting the stoppered cylinder, and allow it to stand at 15
for 5 minutes: the pink color does not entirely disappear.
Amyl alcohol and nonvolatile, carbonizable substances
Allow 25 mL to evaporate spontaneously from a porcelain dish, carefully protected from dust, until the surface of the dish is barely moist: no red or brown color is produced immediately upon the addition of a few drops of sulfuric acid.
Ultraviolet absorbance
Record the UV absorption spectrum between 340 nm and 235 nm in a 1-cm cell, with water in a matched cell in the reference beam: the absorbance is not more than 0.08 at 240 nm, and 0.02 between 270 nm and 340 nm, and the curve drawn through these points is smooth.
Limit of acetone and isopropyl alcohol
To 1.0 mL add 1 mL of water, 1 mL of a saturated solution of dibasic sodium phosphate, and 3 mL of a saturated solution of potassium permanganate. Warm the mixture to 45
to 50
, and allow to stand until the permanganate color is discharged. Add 3 mL of 2.5 N sodium hydroxide, and pass, without washing, through a sintered-glass filter. Prepare a control containing 1 mL of the saturated solution of dibasic sodium phosphate, 3 mL of 2.5 N sodium hydroxide, and 80 µg of acetone in 9 mL. To each solution add 1 mL of furfural solution (1 in 100), and allow to stand for 10 minutes, then to 1.0 mL of each solution add 3 mL of hydrochloric acid: any pink color produced in the test solution is not more intense than that in the control.
Methanol
To 1 drop add 1 drop of water, 1 drop of dilute phosphoric acid (1 in 20), and 1 drop of potassium permanganate solution (1 in 20). Mix, allow to stand for 1 minute, and add sodium metabisulfite solution (1 in 20), dropwise, until the permanganate color is discharged. If a brown color remains, add 1 drop of the dilute phosphoric acid. To the colorless solution add 5 mL of freshly prepared
chromotropic acid TS, and heat on a water bath at 60
for 10 minutes: no violet color appears.
Other requirements
It meets the requirements under
Injections 1.