Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Ammonium Carbonate 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 Ammonium Carbonate provides, in addition to common physical constants, a general description including typical appearance, applications, change in state (approximate), and aqueous solubility. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Assay, Insoluble Matter, Nonvolatile Matter, Chloride, Sulfur Compounds, Heavy Metals, and Iron.
CAS No. 8000-73-5
Note: This product is a mixture of variable proportions of ammonium bicarbonate and ammonium carbamate.
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .
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white powder with odor of ammonia pH adjustment volatilizes at 60 °C 25 g in 100 mL at 15 °C
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . ≥30.0% NH3 Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.005% Nonvolatile matter . . . . . . . . . . . . . . . . . . . 0.01% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 5 ppm Sulfur compounds (as SO4). . . . . . . . . . . . . . . 0.002% Heavy metals (by ICP–OES) . . . . . . . . . . . . . . 5 ppm Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 5 ppm
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4019 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
TESTS Assay (By indirect acid–base titrimetry). Tare a glass-stoppered flask containing about 25 mL of water. Add 2.0–2.5 g of the sample, and weigh accurately. Add slowly 50.0 mL of 1 N hydrochloric acid, and titrate the excess with 1 N sodium hydroxide, using methyl orange indicator. One milliliter of 1 N hydrochloric acid corresponds to 0.01703 g of NH3.
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 20 g dissolved in 100 mL of water.
Nonvolatile Matter To 20 g in a tared, preconditioned dish add 10 mL of water, volatilize on a hot plate (~100 °C), and dry for 1 h at 105 °C. Retain the residue for the test for heavy metals.
Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Dissolve 2.0 g in 25 mL of hot water, add 1.0 mL of sodium carbonate reagent solution, and evaporate to dryness on a hot plate (~100 °C). Dissolve the residue in 20 mL of water.
Sulfur Compounds Dissolve 2.0 g in 20 mL of water, add about 10 mg of sodium carbonate, and evaporate to dryness. Dissolve the residue in a slight excess of hydrochloric acid, add 2 mL of bromine water, and again evaporate to dryness. Dissolve the residue in 4 mL of water plus 1 mL of dilute hydrochloric acid (1:19). Filter through a small filter, wash with two 2 mL portions of water, dilute with water to 10 mL, and add 1 mL of 12% barium chloride reagent solution. Any turbidity should not exceed that produced by 0.04 mg of sulfate ion (SO4) in an equal volume of solution containing the quantities of reagents used in the test. Compare 10 min after adding the barium chloride to the sample and standard solutions.
Heavy Metals ([Part 2: Trace and Ultratrace Elemental Analysis; Inductively Coupled Plasma−Optical Emission Spectroscopy (ICP–OES); Calculation of Heavy Metals (by ICP–OES) Results], by ICP–OES). Use 2.0 g sample.
Iron [Part 2: Colorimetry and Turbidimetry; Iron; Procedure for Iron, Method 1 (Ammonium Thiocyanate)]. To 2.0 g, add 5 mL of water and evaporate on a hot plate (~100 °C). Dissolve the residue in 2 mL of hydrochloric acid, add 20 mL of water, and filter if necessary. Use this solution without further acidification.
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4019 ACS Reagent Chemicals, Part 4
