Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Manganese Sulfate Monohydrate (Manganese(II) Sulfate Monohydrate; Manganous Sulfate Monohydrate) 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 Manganese Sulfate Monohydrate 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, Loss on Ignition, Substances Reducing Permanganate, Insoluble Matter, Chloride, Calcium, Magnesium, Nickel, Potassium, Sodium, Zinc, Heavy Metals, and Iron.
MnSO4 • H2O
Formula Wt 169.01
CAS No. 10034-96-5
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .
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pink or almost white solid preparation of manganese standard solutions dehydrates completely at 400 °C 100 g in 100 mL at 20 °C
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98.0–101.0% MnSO4 · H2O Loss on ignition. . . . . . . . . . . . . . . . . . . . . . 10.0–12.0% Substances reducing permanganate . . . . . . . . . Passes test Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.01% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 0.005% Calcium (Ca) . . . . . . . . . . . . . . . . . . . . . . . 0.005% Magnesium (Mg) . . . . . . . . . . . . . . . . . . . . . 0.005% Nickel (Ni) . . . . . . . . . . . . . . . . . . . . . . . . . 0.02% Potassium (K) . . . . . . . . . . . . . . . . . . . . . . . 0.01% Sodium (Na) . . . . . . . . . . . . . . . . . . . . . . . . 0.05%
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4209 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
Zinc (Zn) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.005% Heavy metals (as Pb) . . . . . . . . . . . . . . . . . . 0.002% Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.002%
TESTS Assay (By complexometric titration of Mn). Weigh accurately about 0.7 g, transfer to a 500 mL beaker, and dissolve in 200 mL of water. Add a few milligrams of ascorbic acid to prevent oxidation. From a burette, add about 30 mL of 0.1 M EDTA volumetric solution, followed by 10 mL of pH 10 ammoniacal buffer reagent solution and about 50 mg of Eriochrome Black T indicator mixture. Continue the titration with 0.1 M EDTA to a clear blue color. One milliliter of 0.1 M EDTA corresponds to 0.01690 g of MnSO4 · H2O.
Loss on Ignition Weigh accurately about 2 g. Ignite to constant weight at 400–500 °C.
Substances Reducing Permanganate Dissolve 7.5 g in 200 mL of water containing 3 mL of sulfuric acid and 3 mL of phosphoric acid. To this solution, add 0.10 mL of 0.1 N potassium permanganate volumetric solution in excess of the amount required to produce a pink color in 200 mL of water containing 3 mL of sulfuric acid and 3 mL of phosphoric acid, and allow to stand for 1 min. The pink color should not be entirely discharged.
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 10 g dissolved in 130 mL of water.
Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Dissolve 1.0 g in 100 mL of water, and use 20 mL of this solution.
Calcium, Magnesium, Nickel, Potassium, Sodium, and Zinc (By flame AAS, [Part 2: Trace and Ultratrace Elemental Analysis; Atomic Absorption Spectroscopy; Analysis; Procedure for Flame AAS]).
For the Determination of Calcium, Magnesium, Nickel, Potassium, Sodium, and Zinc
S a m p l e S t o c k S o l u t i o n . Dissolve 10.0 g in water in a 100 mL volumetric flask, add 0.5 mL of hydrochloric acid, and dilute with water to the mark (1 mL = 0.10 g).
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4209 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
For the Determination of Calcium, Magnesium, Nickel, Potassium, Sodium, and Zinc
Element
Wavelength (nm)
Sample Wt (g)
Standard Added (mg)
Flame Type*
Background Correction
Ca
422.7
0.80
0.02; 0.04
N/A
No
Mg
285.2
0.20
0.005; 0.01
A/A
Yes
Ni
232.0
0.50
0.05; 0.10
A/A
Yes
K
766.5
0.20
0.01; 0.02
A/A
No
Na
589.0
0.02
0.005; 0.01
A/A
No
Zn
213.9
0.20
0.005; 0.01
A/A
Yes
*A/A is air/acetylene; N/A is nitrous oxide/acetylene.
Heavy Metals [Part 2: Colorimetry and Turbidimetry; Heavy Metals (as Lead); Procedure for Heavy Metals, Method 1]. Dissolve 1.0 g in about 20 mL of water, and dilute with water to 25 mL.
Iron [Part 2: Colorimetry and Turbidimetry; Iron; Procedure for Iron, Method 1 (Ammonium Thiocyanate)]. Dissolve 1.0 g in water, dilute with water to 50 mL, and use 25 mL of this solution without further acidification.
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4209 ACS Reagent Chemicals, Part 4
