Magnesium sulfite (MgSO3) is a compound made up of magnesium and sulfite ions. It is commonly used as a food preservative and antioxidant in the food industry.
| IUPAC Name | Magnesium sulfite |
| Molecular Formula | MgSO3 |
| CAS Number | 7757-88-2 |
| Synonyms | Magnesium sulfonate, Magnesium sulfur trioxide, E-536 |
| InChI | InChI=1S/Mg.H2O3S/c;1-4(2)3/h;(H2,1,2,3)/q+2;/p-2 |
Magnesium Sulfite Properties
Magnesium Sulfite Formula
Magnesium sulfite has a chemical formula of MgSO3, which indicates that it is composed of one magnesium atom, one sulfur atom, and three oxygen atoms. The sulfite ion is a polyatomic ion with the formula SO3 2-, consisting of a central sulfur atom bonded to three oxygen atoms. The Mg ion has a charge of +2, while the SO3 2- ion has a charge of -2, making the compound electrically neutral.
Magnesium Sulfite Molar Mass
The molar mass of MgSO3 is 104.37 g/mol, which is the sum of the atomic masses of one magnesium atom, one sulfur atom, and three oxygen atoms. This value is important for calculating the amount of MgSO3 required for a particular reaction, as well as for determining the stoichiometry of chemical equations.
Magnesium Sulfite Boiling Point
MgSO3 decomposes before it reaches its boiling point, so it does not have a specific boiling point. Instead, it begins to break down into magnesium oxide and sulfur dioxide at temperatures above 700°C. This decomposition process can be accelerated by exposure to air or moisture, making MgSO3 a relatively unstable compound.
Magnesium Sulfite Melting Point
The melting point of MgSO3 is approximately 150°C. At this temperature, the compound begins to decompose into magnesium oxide and sulfur dioxide. The decomposition process is exothermic, meaning that it releases heat. The melting point of MgSO3 is important for understanding its properties as a solid, such as its solubility and crystal structure.
Magnesium Sulfite Density g/mL
The density of MgSO3 varies depending on its physical form, but it typically ranges from 2.5 to 3.0 g/mL. This value is important for determining the mass of a given volume of MgSO3, as well as for understanding its behavior in solution. The density of MgSO3 can also be used to calculate its specific gravity, which is a measure of its relative density compared to water.
Magnesium Sulfite Molecular Weight
The molecular weight of MgSO3 is 104.37 g/mol. This value is important for understanding the physical and chemical properties of the compound, as well as for calculating the amount of MgSO3 required for a particular reaction. The molecular weight of MgSO3 can be calculated by adding the atomic weights of one magnesium atom, one sulfur atom, and three oxygen atoms.
Magnesium Sulfite Structure
The structure of MgSO3 is based on a crystal lattice of Mg+2 ions and SO3 2- ions. The Mg+2 ions are surrounded by six oxygen atoms, arranged octahedrally, while the SO3 2- ions are bonded to magnesium ions through two oxygen atoms. The crystal structure of MgSO3 is important for understanding its physical and chemical properties, such as its solubility and reactivity.
Magnesium Sulfite Solubility
MgSO3 is sparingly soluble in water, with a solubility of approximately 7.5 g/L at room temperature. This low solubility is due to the compound’s crystal structure, which makes it difficult for water molecules to penetrate and dissolve the solid. MgSO3 is more soluble in acidic solutions, as the acid can react with the sulfite ion to form bisulfite and sulfurous acid. The solubility of MgSO3 is important for understanding its behavior in solution, as well as for determining its efficacy as a food preservative and antioxidant.
| Appearance | White powder or crystals |
| Specific Gravity | 2.5 – 3.0 |
| Color | White |
| Odor | Odorless |
| Molar Mass | 104.37 g/mol |
| Density | 2.5 – 3.0 g/mL |
| Melting Point | Approximately 150°C |
| Boiling Point | Decomposes above 700°C |
| Flash Point | Not applicable |
| Water Solubility | Sparingly soluble, approximately 7.5 g/L at room temperature |
| Solubility | More soluble in acidic solutions |
| Vapour Pressure | Not applicable |
| Vapour Density | Not applicable |
| pKa | Not applicable |
| pH | Not applicable |
Magnesium Sulfite Safety and Hazards
MgSO3 is not considered to be a highly hazardous substance. However, it can cause irritation to the eyes, skin, and respiratory tract upon contact or inhalation. Ingestion of MgSO3 can cause gastrointestinal irritation and possible vomiting. Prolonged exposure to high concentrations may result in lung damage or respiratory irritation. Therefore, it is important to handle MgSO3 with care, wearing appropriate personal protective equipment and avoiding inhalation of dust or fumes. MgSO3 should be stored in a cool, dry, and well-ventilated area, away from incompatible materials such as strong oxidizers, acids, and bases.
| Hazard Symbols | None |
| Safety Description | Avoid inhalation of dust or fumes. Wear appropriate personal protective equipment. |
| UN IDs | Not regulated |
| HS Code | 2833.29 |
| Hazard Class | Not classified as hazardous |
| Packing Group | Not applicable |
| Toxicity | Low toxicity, can cause irritation to eyes, skin, and respiratory tract upon contact or inhalation. Ingestion can cause gastrointestinal irritation and possible vomiting. Prolonged exposure to high concentrations may result in lung damage or respiratory irritation. |
Magnesium Sulfite Synthesis Methods
One can synthesize MgSO3 through various methods, such as reacting sulfurous acid or sulfur dioxide gas with magnesium oxide or magnesium hydroxide.
In one method, the reaction of magnesium oxide with water forms magnesium hydroxide, which then reacts with sulfurous acid to produce MgSO3.
Another method involves reacting magnesium hydroxide with sulfur dioxide gas in the presence of water to form MgSO3.
In another method, the reaction of magnesium sulfate with sodium sulfite or potassium sulfite can synthesize MgSO3. This reaction produces a precipitate of MgSO3, which researchers can isolate through filtration and drying.
The reaction of magnesium acetate with sulfur dioxide gas in the presence of water can prepare MgSO3. Then, wash and dry the resulting precipitate of MgSO3.
One can use these methods to produce MgSO3 for various applications, including the production of paper and pulp, food and beverage processing, and water treatment.
Magnesium Sulfite Uses
MgSO3 has various uses in different industries. Here are some of its common uses:
- Water treatment: Used as an oxygen scavenger in boiler water treatment to prevent corrosion and scale formation.
- Food and beverage processing: Used as a preservative and antioxidant in food and beverage processing to extend shelf life and prevent spoilage.
- Pulp and paper production: Used as a bleaching agent in the pulp and paper industry to improve the brightness and color of paper products.
- Textile manufacturing: Used as a reducing agent in textile manufacturing to remove excess oxygen and improve the quality of the finished product.
- Agriculture: Used as a foliar spray to improve plant growth and increase crop yields.
- Medicine: Used in traditional medicine for its antioxidant and anti-inflammatory properties.
- Cosmetics: Used in cosmetics as an emulsifier, stabilizer, and pH adjuster.
- Other uses: Also used in the production of adhesives, paints, and coatings, as well as in wastewater treatment processes.
Questions:
Q: What is the formula for magnesium sulfite?
A: The formula for magnesium sulfite is MgSO3.
Q: How much magnesium sulfite is in a 2.4 mol sample?
A: In a 2.4 mol sample of MgSO3, there are 2.4 moles of MgSO3.
Q: What is the mass percent for each element in 1 mole of magnesium sulfite?
A: In one mole of magnesium sulfite, the mass percent of magnesium is 32.44%, sulfur is 29.44%, and oxygen is 38.12%.
Q: Does magnesium sulfite stop muscle cramps?
A: There is no scientific evidence to suggest that MgSO3 can stop muscle cramps. However, magnesium sulfate (Epsom salt) has been used for this purpose.
Q: What does addition of magnesium sulfite do in reactions?
A: The addition of MgSO3 can act as a reducing agent in some reactions by removing oxygen. It can also act as a preservative and antioxidant in certain applications.
Q: Is magnesium sulfite ionic or molecular?
A: MgSO3 is an ionic compound.