Monograph pubs.acs.org/doi/book/10.1021/acsreagents
(Ethylenedinitrilo)tetraacetic Acid, Magnesium Disodium Salt (Disodium Magnesium EDTA; EDTA (Magnesium Disodium 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 (Ethylenedinitrilo)tetraacetic Acid, Magnesium Disodium Salt 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 Stoichiometry.
(NaO2CCH2)2NC2H4N(CH2- Formula Wt 358.50 CO2)2Mg
CAS No. 14402-88-1
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . white solid Applications . . . . . . . . . . . . . . . . . . . . . . . . chelating agent
SPECIFICATIONS Clarity of solution . . . . . . . . . . . . . . . . . . . . Passes test Stoichiometry. . . . . . . . . . . . . . . . . . . . . . . Passes test
TESTS Clarity of Solution Dissolve 5 g in 100 mL of water. The solution should be clear and colorless with no more than a faint trace of turbidity.
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4141 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
Stoichiometry To the solution from the clarity of solution test, add 0.1 mL of calmagite indicator solution and 5 mL of pH 10 ammoniacal buffer solution. The solution should be a light blue color with a red tint. Add 0.10 mL of 0.01 M EDTA. The color should be blue. Add 0.20 mL of 0.01 M calcium standard solution (described below), and the solution should change to red.
For the Determination of Stoichiometry
C a l c i u m S t a n d a r d S o l u t i o n , 0 . 0 1 M . Dissolve 0.100 g of calcium carbonate in 2 mL of 10% hydrochloric acid in a 100 mL volumetric flask. Dilute to the mark with water.
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4141 ACS Reagent Chemicals, Part 4