Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Barium Diphenylamine Sulfonate (Diphenylamine-4-sulfonic Acid, Barium Salt) 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 Barium Diphenylamine Sulfonate provides, in addition to common physical constants, a general description including typical appearance, applications, and aqueous solubility. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Residue after Ignition, Clarity of Solution, and Sensitivity as Redox Indicator.
C24H20BaN2O6S2
Formula Wt 633.88
CAS No. 6211-24-1
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . white to gray solid Applications . . . . . . . . . . . . . . . . . . . . . . . . indicator for redox titrations Aqueous solubility . . . . . . . . . . . . . . . . . . . . slightly soluble
SPECIFICATIONS Residue after ignition (as sulfate) . . . . . . . . . . 35.0–38.0% Clarity of solution . . . . . . . . . . . . . . . . . . . . Passes test Sensitivity as redox indicator . . . . . . . . . . . . . Passes test
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4047 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
TESTS Residue after Ignition Accurately weigh 1.0 g in a preconditioned, tared crucible. Add 2 mL of sulfuric acid in 5 mL of water, and swirl gently. Using a high temperature setting, heat on a hot plate until fuming ceases. Ignite at 800 ± 25 °C until a white residue is obtained. Cool and weigh.
Clarity of Solution Weigh 0.15 g, and dissolve in 100 mL of water by heating. The solution should be complete and colorless. Reserve this solution for test for sensitivity as redox indicator.
Sensitivity as Redox Indicator To 25 mL of water in a 50 mL test tube, add 10 mL of 4 N sulfuric acid, 5 mL of phosphoric acid, 0.05 mL of 0.01 N ferrous ammonium sulfate, and 0.05 mL of the solution reserved from the clarity of solution test. The addition of 0.10 mL of 0.01 N potassium dichromate should produce a violet color. The color should be completely discharged by the addition of 0.10 mL of 0.01 N ferrous ammonium sulfate.
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4047 ACS Reagent Chemicals, Part 4
