Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Benzoyl Chloride Part 4, Monographs for Reagent Chemicals: General Descriptions, Specifications, and Tests eISBN: 9780841230460 Tom Tyner Chair, ACS Committee on Analytical Reagents James Francis Secretary, ACS Committee on Analytical Reagents
ABSTRACT This monograph for Benzoyl Chloride provides, in addition to common physical constants, a general description including typical appearance, applications, change in state (approximate), aqueous solubility, and density. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Assay, Freezing Point, Residue after Ignition, Phosphorus Compounds, Heavy Metals, and Iron.
C6H5COCl
Formula Wt 140.57
CAS No. 98-88-4
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . . Density . . . . . . . . . . . . . . . .
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clear, fuming liquid with a pungent odor derivatizing agent boiling point, 198 °C decomposes in water 1.21
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98.0–100.5% C6H5COCl Freezing point . . . . . . . . . . . . . . . . . . . . . . –2.0 to 0.0 °C Maximum Allowable Residue after ignition. . . . . . . . . . . . . . . . . . 0.005%
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4054 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
Phosphorus compounds (as P). . . . . . . . . . . . . 0.002% Heavy metals (as Pb) . . . . . . . . . . . . . . . . . . 0.001% Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.001%
TESTS Assay (By acid–base titrimetry). Weigh accurately about 2 mL in a glass-stoppered flask, add 50.0 mL of 1 N sodium hydroxide volumetric solution, and stopper the flask. Allow to stand, with frequent agitation, until the sample has dissolved. Add 0.15 mL of phenolphthalein indicator solution, and titrate the excess sodium hydroxide with 1 N hydrochloric acid. One milliliter of 1 N sodium hydroxide corresponds to 0.07028 g of C6H5COCl.
Freezing Point Place 15 mL in a test tube (20 mm × 150 mm) in which is centered an accurate thermometer. Center the sample tube by corks in an outer tube about 38 mm × 200 mm. Cool the whole apparatus, without stirring, in a bath of shaved or crushed ice mixed with sufficient salt and water to provide a temperature of –5 °C. When the temperature is about –2 °C, stir to start the freezing and read the thermometer every 30 s. The temperature that remains constant for 1–2 min is the freezing point.
Residue after Ignition [Part 2: Gravimetric Methods; Residue after Ignition]. Evaporate 40 g (33 mL) to dryness in a tared, preconditioned dish, adding sufficient sulfuric acid to wet the sample. Add to the carbonized mass 2 mL of nitric acid and 0.25 mL of sulfuric acid, and heat cautiously until white fumes of sulfur trioxide are no longer evolved. Ignite at 800 °C for 1 h. Retain the residue to prepare sample solution A for the determination of heavy metals and iron.
Phosphorus Compounds To 1 g (0.85 mL), add 7 mL of water and 3 mL of nitric acid. Heat the mixture to boiling, boil for 2 min, cool, dilute with water to 20 mL, and filter. To 10 mL of the filtrate, add 5 mL of 10% sulfuric acid reagent solution, and evaporate to fumes of sulfur trioxide. Cool, dilute with water to 25 mL, add 1 mL of ammonium molybdate reagent solution and 1 mL of 4(methylamino)phenol sulfate reagent solution, and allow to stand for 2 h at room temperature. Any blue color should not exceed that produced by 0.03 mg of phosphate ion (PO4) in an equal volume of solution containing the quantities of reagents used in the test.
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For the Determination of Heavy Metals and Iron
S a m p l e S o l u t i o n A . Add 10 mL of 10% hydrochloric acid reagent solution to the residue obtained in the test for residue after ignition, and evaporate to dryness on a hot plate (~100 °C). Dissolve the residue in 0.5 mL of hydrochloric acid and 25 mL of hot water, filter if necessary, and dilute with water to 200 mL (1 mL = 0.2 g).
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4054 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
Heavy Metals
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[Part 2: Colorimetry and Turbidimetry; Heavy Metals (as Lead); Procedure for Heavy Metals, Method 1]. Use 10 mL of sample solution A (2 g sample).
Iron† [Part 2: Colorimetry and Turbidimetry; Iron; Procedure for Iron, Method 1 (Ammonium Thiocyanate)]. Use 5.0 mL of sample solution A (1 g sample).
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4054 ACS Reagent Chemicals, Part 4
