Specifications of Manganese Chloride Tetrahydrate USP Grade

MnCl2.4H2O --- 197.90
Manganese (2+) chloride tetrahydrate CAS 13446-34-9
Anhydrous 125.84 CAS 7773-01-5

Manganese Chloride contains not less than 98.0 percent and not more than 101.0 percent of MnCl2, calculated on the dried basis.

Identification:
A: Yields white, curdy precipitate of silver chloride with silver nitrate TS, which is insoluble in nitric acid. After being washed with water, this precipitate is soluble in a slight excess of 6 N ammonium hydroxide.
B: It meets the requirements of the test for Manganese.
pH: between 3.5 and 6.0, 10 g dissolved in 200 mL of carbon dioxide- and ammonia-free water being used.
Loss on drying: Dry it at 50 for 2 hours, then raise the temperature to 150 for 24 hours: it loses between 36.0% and 38.5% of its weight.
Insoluble matter: Transfer 10 g to a 250-mL beaker, add 150 mL of water, cover the beaker, and heat to boiling. Digest the hot solution on a steam bath for 1 hour, and pass through a tared, fine-porosity filtering crucible. Rinse the beaker with hot water, passing the rinsings through the filter, and finally wash the filter with additional hot water. Dry the filter at 105C: the residue weighs not more than 0.5 mg (0.005%).
Sulfate: A 2.0 g portion shows no more sulfate than corresponds to 0.10 mL of 0.020 N sulfuric acid (0.005%).
Substances not precipitated by ammonium sulfide: Dissolve 2.0 g in about 90 mL of water, add 5 mL of ammonium hydroxide, and warm the solution to about 80C. Pass a stream of hydrogen sulfide through the solution for 30 minutes. Dilute with water to 100 mL, mix, and allow the precipitate to settle. Decant the supernatant through a fine-porosity filter, and transfer 50.0 mL to an evaporating dish that previously has been ignited and tared. Evaporate the filtrate to dryness, cool, add 0.5 mL of sulfuric acid, heat gently to remove the excess acid, and ignite at 800C ± 25C for 15 minutes: the weight of the residue is not greater than 2.0 mg (0.2% as sulfate).
Iron: Dissolve 2.0 g in 40 mL of water: the limit is 5 µg per g.
Zinc: Dissolve 1 g in a mixture of 48 mL of water and 2 mL of sulfuric acid, and add, slowly and with constant agitation, 1 mL of potassium ferrocyanide solution (1 in 100): no turbidity is produced within 5 minutes.
Heavy metals: the limit is 5 µg per g.

Specifications of Manganese Chloride Tetrahydrate Analytical Reagent Grade Molecular Formula: MnCl2-4H2O
Molecular Weight: 197.90
CAS Number 13446-34-9

REQUIREMENTS
Assay: 98.0-101.0% MnCl2-4H2O
pH of a 5% solution: 3.5-6.0 at 25C

MAXIMUM ALLOWABLE
Insoluble matter: 0.005%
Sulfate (SO4): 0.005%
Heavy metals (as Pb): 5 ppm
Iron (Fe): 5 ppm
Calcium (Ca): 0.005%
Magnesium (Mg): 0.005%
Potassium (K): 0.01%
Sodium (Na): 0.05%
Zinc (Zn): 0.005%

DESCRIPTION
It occurs as large, irregular, pink, translucent crystals. It is freely soluble in water at room temperature and very soluble in hot water.
Function: Nutrient.

REQUIREMENTS
Identification: A 1:20 aqueous solution gives positive tests for Manganese and for Chloride.
Assay: Not less than 98.0% and not more than 102.0% of MnCl2-4H2O.
Insoluble Matter: Not more than 0.005%.
Iron: Not more than 5 mg/kg.
Lead: Not more than 4 mg/kg.
pH of a 5% Solution: Between 4.0 and 6.0.
Substances Not Precipitated by Sulfide: Not more than 0.2%, after ignition.
Sulfate: Not more than 0.005%.