Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Zincon (2-{[α-(2-Hydroxy-5-sulfophenylazo)-benzylidene]-hydrazino}-benzoic Acid Monosodium Salt)
Downloaded by CORNELL UNIV on May 15, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.4430
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 Zincon provides, in addition to common physical constants, a general description including typical appearance and applications. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Clarity of Solution and Suitability for Complexometric Titration.
C20H15N4NaO6S (anhydrous) C20H15N4NaO6S• H2O (monohydrate)
Formula Wt 462.41
CAS No. 62625-22-3
Formula Wt 480.43
Note: This standard applies to both the anhydrous and monohydrate form of the indicator.
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . purple solid Applications . . . . . . . . . . . . . . . . . . . . . . . . reagent for zinc, mercury, and copper
© 2017 American Chemical Society
A
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4430 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
SPECIFICATIONS Clarity of solution . . . . . . . . . . . . . . . . . . . . Passes test Suitability for complexometric titration (Zn) . . . Passes test
TESTS Clarity of Solution Weigh 0.10 g, and dissolve in 100 mL of water. Not more than a faint trace of turbidity or insoluble matter should remain. Reserve the solution for the suitability for complexometric titration test.
Downloaded by CORNELL UNIV on May 15, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.4430
Suitability for Complexometric Titration To 25 mL of water, add 5 mL of pH 10 ammoniacal buffer solution and 0.10 mg of zinc ion. Add 0.5 mL of solution from the test for clarity of solution. A blue color develops. Add 0.10 mL of 0.1 M EDTA volumetric solution. The solution should become red.
© 2017 American Chemical Society
B
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.4430 ACS Reagent Chemicals, Part 4
