Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Ammonium Bromide 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
Downloaded via UNIV OF SASKATCHEWAN on August 20, 2019 at 23:19:02 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.
A u t h o r i t a t i v e V e r s i o n : This version is current as of 01 Jun 2016.
ABSTRACT This monograph for Ammonium Bromide 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, pH of a 5% Solution at 25.0 °C, Insoluble Matter, Residue after Ignition, Bromate, Chloride, Iodide, Sulfate, Barium, Heavy Metals, and Iron.
NH4+
NH4Br
Br-
Formula Wt 97.94
CAS No. 12124-97-9
SUPPLEMENTS & UPDATES Published
Authoritative
28 Feb 2017
01 Jun 2016
Expired
Type
Summary
Other Versions
Original
First on-line publication, based on 11th ed.
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
© 2017 American Chemical Society
white solid photochemical reactions; precipitation of silver salts sublimation point, 542 °C 68 g in 100 mL at 10 °C
A
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4018.20160601 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . ≥99.0% NH4Br pH of a 5% solution at 25.0 °C . . . . . . . . . . . . 4.5–6.0
Insoluble matter . . . . . . . Residue after ignition. . . . Bromate (BrO3) . . . . . . . . Chloride (Cl) . . . . . . . . . Iodide (I). . . . . . . . . . . . Sulfate (SO4) . . . . . . . . . Barium (Ba) . . . . . . . . . . Heavy metals (by ICP–OES) Iron (Fe) . . . . . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
Maximum Allowable 0.005% 0.01% 0.002% 0.2% Passes test 0.005% 0.002% 5 ppm 5 ppm
TESTS Assay (By indirect argentimetric titration of bromide). Weigh accurately about 0.4 g of sample in 50 mL of water. Add 10 mL of 10% nitric acid reagent solution and 50.0 mL of 0.1 N silver nitrate volumetric solution, and titrate the excess silver nitrate with 0.1 N ammonium thiocyanate volumetric solution, using 0.5 mL of ferric sulfate reagent solution as an indicator. One milliliter of 0.1 N silver nitrate consumed corresponds to 0.009794 g of NH4Br. % NH4Br =
[(50.0 × N AgNO3)
(mL × N NH4SCN)] × 9.794 Sample wt (g)
pH of a 5% Solution at 25.0 °C [Part 2: Direct Electrometric Methods; pH Potentiometry; pH Range; Procedure for pH of a 5% Solution at 25.0 °C].
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 20 g dissolved in 150 mL of water.
Residue after Ignition [Part 2: Gravimetric Methods; Residue after Ignition]. Ignite 20 g.
Bromate [Part 2: Direct Electrometric Methods; Specific Polarographic Procedures; Polarographic Procedure for Bromate and Iodate]. Use 5.0 g of sample in 25 mL of solution. For the standard, add 0.10 mg of bromate ion (BrO3).
Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Dissolve 0.50 g in 15 mL of dilute nitric acid (1:2) in a small flask. Add 3 mL of 30% hydrogen peroxide and digest on a hot plate (~100 °C) until the solution is colorless. Wash down the sides of the flask
© 2017 American Chemical Society
B
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4018.20160601 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
with a little water, digest for an additional 15 min, cool, and dilute with water to 200 mL. Dilute 2.0 mL of the solution with water to 20 mL.
Iodide Dissolve 5.0 g in 20 mL of water. Add 1 mL of chloroform, 0.15 mL of 10% ferric chloride reagent solution, and 0.25 mL of 10% sulfuric acid, and shake for 1 min. No violet tint should be produced in the chloroform. (Limit about 0.005%.)
Sulfate [Part 2: Colorimetry and Turbidimetry; Sulfate; Procedure for Sulfate, Method 1]. Allow 30 min for turbidity to form.
Barium For the sample, dissolve 6.0 g in 15 mL of water. For the control, dissolve 1.0 g in 15 mL of water, and add 0.1 mg of barium. To each solution, add 5 mL of glacial acetic acid, 5 mL of 30% hydrogen peroxide, and 1 mL of hydrochloric acid. Digest in a covered beaker on a hot plate (~100 °C) until reaction ceases, uncover, and evaporate to dryness. Dissolve each residue in 15 mL of water, filter if necessary, and dilute with water to 23 mL. Add 2 mL of 10% potassium dichromate reagent solution, then add ammonium hydroxide until the orange color is just dissipated and the yellow color persists. Add 25 mL of methanol, stir vigorously, and allow to stand for 10 min. Any turbidity in the solution of the sample should not exceed that in the control.
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)]. Use 2.0 g.
© 2017 American Chemical Society
C
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4018.20160601 ACS Reagent Chemicals, Part 4
