Trichloromonofluoromethane
»Trichloromonofluoromethane contains not less than 99.6percent and not more than 100.0percent of CCl3F,calculated on the anhydrous basis.
Packaging and storage
Preserve in tight cylinders,and avoid exposure to excessive heat.
Identification
The IRabsorption spectrum of it,determined in a 10-cm cell with sodium chloride windows,at atmospheric pressure,exhibits maxima,among others,at the following wavelengths,in µm:4.67(m),5.95(m),7.28(s),8.06(m),9.2(vs),10.7(vs),11.8(vs),and 13.4(m).The stronger maxima are best obtained at pressures less than 10mm of mercury.
Boiling temperature:
approximately 24,determined as directed under Approximate Boiling Temperature(see Aerosols,Nasal Sprays,Metered-Dose Inhalers,and Dry Powder Inhalers á601ñ).
Water:
not more than 0.001%,determined as directed under Water Content(see Aerosols,Nasal Sprays,Metered-Dose Inhalers,and Dry Powder Inhalers á601ñand Method Icunder Water Determination á921ñ).
High-boiling residues:
not more than 0.01%,determined as directed for High-Boiling Residues,Method I,under Aerosols,Nasal Sprays,Metered-Dose Inhalers,and Dry Powder Inhalers á601ñ.
Chromatographic purity
In the chromatogram recorded for the Assay,identify the peaks due to dichlorodifluoromethane and dichlorotetrafluoroethane from relative retention times observed on chromatographing the Resolution preparation:the sum of these two peak areas is not greater than 0.2%of the total of all peak areas;and the sum of the areas of all peaks other than that for trichloromonofluoromethane is not greater than 0.4%of the total of all peak areas.
Inorganic chlorides
Place 5mLof anhydrous methanol in a test tube,add 3drops of a saturated solution of silver nitrate in anhydrous methanol,shake,and add 7g of Trichloromonofluoromethane:no opalescence or turbidity is produced.
Assay
Resolution preparation
and Chromatographic systemProceed as directed in the Assayunder Dichlorodifluoromethane.
Assay preparation
Introduce the liquid phase of Trichloromonofluoromethane into an evacuated headspace vial.
Procedure
Inject the gas phase headspace Assay preparationinto the chromatograph,record the chromatogram,and measure the peak areas.Calculate the percentage (a/a)of CCl3Fin the portion of Trichloromonofluoromethane taken.
Auxiliary Information
Staff Liaison:Karen A Russo,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28NF23Page 3100
Pharmacopeial Forum:Volume No.27(1)Page 1825
Phone Number:1-301-816-8379
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