Manganese Sulfate Monohydrate: Properties, Uses & Lab Guide

Manganese sulfate monohydrate is a water-soluble inorganic salt of manganese(II) that serves as a versatile reagent in research, agriculture, and industrial applications, including use as a colorant in dyes and as a source of bioavailable manganese.

Chemical Name

Manganese(II) sulfate monohydrate

Molecular Formula

MnSO₄·H₂O

SKU

M111707B

Solubility

Readily soluble in water

Primary Applications

Colorant in dyes, trace element supplement, industrial and research reagent

Natural Occurrence

Found in earth's crust, atmosphere (dust, volcanic activity, forest fires), foods, and drinking water

Chemical Identity and Physical Properties

Manganese sulfate monohydrate (MnSO₄·H₂O) is the monohydrated form of manganese(II) sulfate, an inorganic salt in which manganese exists in the +2 oxidation state. It typically appears as a pale pink to off-white crystalline powder and is highly soluble in water, forming clear, light-pink solutions. The compound is stable under normal laboratory storage conditions and is one of the most commercially important manganese salts due to its ready solubility and bioavailability.

Manganese is one of the most abundant transition metals found in the earth's crust and enters the environment through natural processes—including dust transport, volcanic activity, and forest fires—as well as through industrial emissions. It is also naturally present in many foods and in drinking water supplies.

Applications in Research and Industry

Manganese sulfate monohydrate has a broad range of applications across research, agriculture, and industry:

• Colorant in dyes: The compound is used as a colorant and mordant in dye formulations, imparting characteristic coloration and aiding dye fixation to substrates.
• Trace element supplementation: As a bioavailable source of Mn²⁺, it is employed in cell culture media, microbiological growth media, and plant nutrient solutions where manganese is an essential micronutrient.
• Analytical chemistry: Manganese sulfate serves as a reagent in titrimetric and colorimetric assays, including the Winkler method for dissolved oxygen determination.
• Catalyst and oxidation reactions: Mn(II) ions act as catalysts or co-catalysts in various oxidation reactions in synthetic chemistry.
• Agricultural fertilizers: It is used to correct manganese deficiency in soils and as a foliar spray micronutrient supplement.

Safe Handling and Storage Guidelines

When working with manganese sulfate monohydrate in the laboratory, researchers should observe the following precautions:

• Personal protective equipment (PPE): Wear appropriate lab coat, chemical-resistant gloves, and safety goggles. Avoid generating dust during weighing or transfer operations.
• Inhalation precautions: Manganese-containing dusts and fumes are associated with neurological effects upon chronic occupational exposure. Work in a well-ventilated area or fume hood when handling powder forms.
• Storage: Store in a cool, dry, well-ventilated location in a tightly sealed container, away from incompatible materials. Keep away from strong oxidizers.
• Disposal: Dispose of manganese-containing waste in accordance with local regulations. Do not pour solutions containing manganese ions down the drain without authorization, as manganese is an aquatic environmental hazard.
• First aid: In case of skin or eye contact, flush thoroughly with water. If inhaled, move to fresh air. Consult the Safety Data Sheet (SDS) for full guidance.

Always consult the current SDS for product-specific hazard information before use.

Preparation of Aqueous Solutions

Manganese sulfate monohydrate dissolves readily in water and is commonly prepared as stock solutions for use in analytical, biological, or agricultural applications. Follow these general steps:

1. Calculate the required mass: Use the molecular weight of MnSO₄·H₂O (MW = 169.02 g/mol; verify with current CoA) and the target concentration to determine the mass needed.
2. Weigh accurately: Tare a clean, dry weighing boat or container on an analytical balance. Weigh the appropriate amount of the powder, minimizing dust exposure.
3. Dissolve: Transfer the weighed compound to an appropriate volumetric flask. Add approximately 80% of the final volume of ultrapure (Type 1) water and mix until fully dissolved.
4. Adjust to final volume: Make up to the final volume with ultrapure water and mix thoroughly.
5. Filter if required: For cell culture or sensitive biological applications, filter through a 0.22 µm membrane filter to sterilize.
6. Label and store: Label the solution with compound name, concentration, date of preparation, and expiry. Store at room temperature unless otherwise specified.

Note: Verify the exact molecular weight from the Certificate of Analysis (CoA) supplied with your specific lot before performing critical calculations.

Frequently asked questions

What is manganese sulfate monohydrate used for in the laboratory?

Manganese sulfate monohydrate is used as a source of Mn²⁺ ions in cell culture media, microbiological growth media, and analytical reagent preparations. It is also employed as a colorant in dyes and as a catalyst component in oxidation reactions.

How should manganese sulfate monohydrate be stored?

Store manganese sulfate monohydrate in a tightly sealed container in a cool, dry, and well-ventilated area, away from strong oxidizers and moisture. Always refer to the product's Safety Data Sheet for specific storage conditions.

Is manganese sulfate monohydrate hazardous?

Manganese sulfate monohydrate should be handled with care. Chronic inhalation of manganese-containing dusts is associated with neurological effects in occupational settings. Appropriate PPE including gloves, goggles, and lab coat should be worn, and powder handling should be performed in a well-ventilated area or fume hood. Consult the SDS for full hazard information.

Where does manganese occur naturally?

Manganese is one of the most abundant elements in the earth's crust. It enters the atmosphere from dust, volcanic activity, forest fires, and industrial emissions, and is also naturally present in many foods and in drinking water.

What is the molecular formula and molecular weight of manganese sulfate monohydrate?

The molecular formula of manganese sulfate monohydrate is MnSO₄·H₂O. The molecular weight is approximately 169.02 g/mol; however, always verify this value against the Certificate of Analysis (CoA) for your specific lot.

References

1. Aladdin Scientific. Manganese sulfate monohydrate product description. SKU M111707B.
2. Greenwood, N.N.; Earnshaw, A. Chemistry of the Elements, 2nd ed. Butterworth-Heinemann, 1997. Chapter on Manganese.
3. World Health Organization. Manganese in Drinking Water: Background Document for Development of WHO Guidelines for Drinking-Water Quality.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.