Sodium Diethyldithiocarbamate Trihydrate - ACS Reagent Chemicals

Feb 28, 2017 - Moisten the sample with concentrated sulfuric acid, and ignite cautiously to char the material. Finally, ignite to constant weight at 8...
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Monograph pubs.acs.org/doi/book/10.1021/acsreagents

Sodium Diethyldithiocarbamate Trihydrate 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 Sodium Diethyldithiocarbamate Trihydrate 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: Solubility in Water, Sodium, and Sensitivity to Copper.

(CH3CH2)2NCS2Na • 3H2O Formula Wt 225.30

CAS No. 20624-25-3

GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .

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white or colorless solid reagent for copper melting point, 94–96 °C after drying freely soluble with gradual decomposition

SPECIFICATIONS Solubility in water . . . . . . . . . . . . . . . . . . . . Passes test Sodium (as Na2SO4) . . . . . . . . . . . . . . . . . . . 30.5%–32.5% Sensitivity to copper . . . . . . . . . . . . . . . . . . Passes test

TESTS Solubility in Water Dissolve 1 g in 50 mL of water. There should be no undissolved residue, and the solution should be substantially clear. Retain the solution for the test for sensitivity.

© 2017 American Chemical Society

A

DOI:10.1021/acsreagents.4345 ACS Reagent Chemicals, Part 4

ACS Reagent Chemicals

Monograph

pubs.acs.org/doi/book/10.1021/acsreagents

Note: Because of inherent instability, this reagent may be expected to react with oxygen in the atmosphere to form insoluble oxidation products. After storage for some time, the reagent may fail to meet the requirement for solubility in water.

Sodium Weigh accurately 2 g in a tared, preconditioned dish or crucible. Moisten the sample with concentrated sulfuric acid, and ignite cautiously to char the material. Finally, ignite to constant weight at 800 ± 25 °C.

Sensitivity to Copper

For the Determination of Sensitivity to Copper

S o l u t i o n A . Dilute 5 mL of the solution retained from the test for solubility in water to 100 mL with water.

For the sample, prepare a solution containing 0.002 mg of copper ion (Cu) in 100 mL of dilute ammonium hydroxide (1:99). For the control, use 100 mL of dilute ammonium hydroxide (1:99). Transfer the solutions to separatory funnels and add to each 10 mL of solution A and 10 mL of isopentyl alcohol. Shake for about 1 min and allow to separate (about 30 min). The isopentyl alcohol separated from the solution containing the 0.002 mg of copper should show a distinct yellow color when compared with the isopentyl alcohol from the control.

© 2017 American Chemical Society

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DOI:10.1021/acsreagents.4345 ACS Reagent Chemicals, Part 4