FCCV标准-Sodium Pyrophosphate焦磷酸钠.pdf

IECC V
Monographs / Sodium Pyrophosphate /431
in moist air. One gram is soluble in about I ML of water at Sodium Pyrophosphate
25, in about 0.65 ML of boiling water, and in about 24 ML
of alcohol. The PH of a 1: 10 aqueous solution is between 8.0 Tetrasodium Diphosphate; Tetrasodium Pyrophosphate
and 10.5
Na4p2 O
ormula wl, anhydrous 265.90
Function Preservative mold inhibitor
Na4p207' 10H, O
Formula wl, decahydrate 446.06
INS: 450(111
CAS: anhydrous 7722-88-5
REQUIREMENTS
CAS: decahydrate 13472-36-1I
Identification
A. A 1: 20 aqueous solution gives positive tests for Sodium
Appendix IIA
DESCRIPTION
B. Upon ignition, a sample yields an alkaline residue that Sodium Pyrophosphate occurs as colorless or white crystals
th acids
or as a white, crystalline or granular powder. It is anhydrous or
C. Warm a small sample with sulfuric acid. Propionic acid, contains 10 molecules of water ofhydration. The decahydrate
recognized by its odor, evolves
effloresces slightly in dry air. It is soluble in water, bul is
Assay Not less than 99 0 and not more than 100. 5% of insoluble in alcohol. The PH of a 1: 100 aqueous solution is
C:HSNA0 2 after drying
aboul 10
Alkalinity (as NA2CO3)Passes test(about 0.15%0
ron Not more than 0.0
Function Emulsifier; buffer: nutrient; sequestrant; tex
Lead Not more than 2 mg/k
uui∠er
Water Nol more than 100
REQUIREMENTS
TESTS
Identification
Assay Dissolve about 250 mg of sample, previously dried A. A 1: 20 aqueous solution gives positive tests for Sodium
at 105 for I h and accurately weighed, in 40 ML o! glacial Appendix IIIA
acetic acid, warming if necessary to effect solution. Cool to B. Dissolve 100 mg of sample in 100 ml of 1.7 N nitric
room temperature, add 2 drops of crystal violet TS, and titrate acid. Add 0.5 ml of this solution to 30 ml of quimociac TS
with 0.1 N perchloric acid
A yellow precipitate does not form. Heal the remaining porlion
Caution: Handle perchloric acid in an appropriate
ol the sample solution for 10 min al 95, and then add 0.5
fume hood
ML of the solution to 30 ML of quimociac TS. A yellow
precipitate forms immediately
Perform a blank determination (see(eneral Provisions), and Assay Not less than 95. 0%and not more than 100.5%o
make any necessary correction. Each milliliter of 0.1 N per-na4po-. calculated on the ignited basis
chloric acid is equivalent to 9. 606 mg of C Hsna02
Arsenic Not more than 3 mg/kg
Alkalinity (as Na2 CO ) Dissolve 4 g of sample in 20 ML Fluoride Not more than.005%
of water, and add 3 drops of phenolphthalein TS. If a pink Insoluble Substances Not more than 0.2/
color appears, not more than 0.6 ml of 0.1 W sulfuric acid Lead Not more than 4 mg/kg
is required to discharge 1
Loss on Ignition An/ydrolis: Not more than 0.5% ecahy-
Iron Dissolve 300 mg of sample in 40 ML of water, and drate. Between 38.0% and 4200
add 2 ML of hydrochloric acid, about 40 mg of ammonium
persulfate, and 10 ml of ammonium thiocyanate TS Any red
TESTS
produced by
Iron Stanard oltion (9 pg Pe, see Solutions and Indcators)Assay Dissolve an accurately weighed quantity of the sam
in an equal volume of solution containing the quantites of ple, equivalent to 500 mg of anhydrous Nap,O, in 100