Na2s205

Decoding Na₂S₂O₅: Unveiling the Secrets of Sodium Metabisulfite

Sodium metabisulfite (Na₂S₂O₅), often encountered in the food industry and various other applications, might sound intimidating, but understanding its properties and uses is simpler than you think. This article breaks down the complexities of Na₂S₂O₅, providing a clear and concise explanation suitable for everyone, from curious home cooks to professionals in related fields.

1. Chemical Composition and Structure

Na₂S₂O₅, chemically named sodium metabisulfite, is an inorganic compound. It's essentially a salt formed from the combination of sodium (Na) and metabisulfite (S₂O₅²⁻) ions. The metabisulfite ion itself is a dimer of bisulfite ions (HSO₃⁻), meaning two bisulfite units are linked together. You can visualize it as two pyramids sharing a corner, representing the sulfur atoms connected through an oxygen bridge. This structural feature is crucial to its reactivity.

Understanding the chemical formula itself is crucial. The "2" before Na indicates two sodium atoms are present in each molecule, balancing the -2 charge of the metabisulfite ion. This balanced charge contributes to its stability in solid form.

2. Properties and Reactivity

Sodium metabisulfite is a white, crystalline powder that readily dissolves in water. Its most important property stems from its ability to release sulfur dioxide (SO₂) when dissolved in water or exposed to acidic conditions. This reaction is crucial for many of its applications:

Na₂S₂O₅ + H₂O → 2 Na⁺ + 2 HSO₃⁻ (in water)
2 HSO₃⁻ + 2 H⁺ → 2 SO₂ + 2 H₂O (in acidic conditions)

The liberated sulfur dioxide is a potent reducing agent, meaning it readily donates electrons to other substances. This reduction property is the key to its various uses.

3. Applications in Food Preservation

One of the most common uses of sodium metabisulfite is as a food preservative. Its antioxidant and antimicrobial properties are invaluable in extending the shelf life of various foods. The released sulfur dioxide acts as:

Antioxidant: It prevents oxidation, which causes food spoilage by reacting with oxygen and preventing it from damaging the food. This is particularly crucial in preventing browning in fruits and vegetables. Think of the clear juice of bottled lemon juice, which owes its freshness partly to sodium metabisulfite.

Antimicrobial: The sulfur dioxide inhibits the growth of bacteria, yeasts, and molds. This is vital in maintaining the quality and safety of foods, preventing unwanted microbial activity that could spoil or contaminate products like dried fruits, wine, and some processed meats.

For example, in winemaking, it is used to sanitize equipment and prevent unwanted microbial growth during fermentation. In dried fruits, it acts as an antimicrobial agent preventing mold growth, extending their shelf life.

4. Other Industrial Applications

Beyond food preservation, Na₂S₂O₅ finds applications in diverse industries:

Photography: It's used as a preservative in photographic solutions.

Textile Industry: It's a bleaching agent and is used in the treatment of wool and silk.

Pulp and Paper Industry: It aids in the bleaching process.

Water Treatment: It's used as a dechlorinating agent to remove chlorine from water.

These diverse applications highlight the versatility of this compound based on its reducing and antimicrobial properties.

5. Safety Precautions and Handling

While generally safe in controlled environments and within regulatory limits for food applications, Na₂S₂O₅ can pose some risks. Direct contact with skin and eyes should be avoided, and proper respiratory protection is necessary when handling large quantities due to potential SO₂ release. It's crucial to follow manufacturer instructions and relevant safety regulations. Ingestion of large amounts can lead to adverse health effects. Always ensure proper ventilation when using it.

Key Takeaways

Sodium metabisulfite is a versatile inorganic compound with crucial applications, primarily as a food preservative and industrial reducing agent. Its effectiveness stems from its ability to release sulfur dioxide, which acts as an antioxidant and antimicrobial agent. However, proper handling and safety precautions are essential to minimize potential risks.

FAQs

1. Is sodium metabisulfite harmful to human health? In small amounts, as permitted in food, it's generally considered safe. However, large doses can cause adverse health effects.

2. Can I use sodium metabisulfite at home for food preservation? Yes, but it's crucial to follow guidelines for safe usage and comply with relevant food safety regulations.

3. What are the alternatives to sodium metabisulfite? Depending on the application, alternatives include other sulfites, ascorbic acid (vitamin C), or other preservatives.

4. How is sodium metabisulfite disposed of? Dispose of it according to local regulations. Never pour it down the drain without neutralizing it first.

5. What is the difference between sodium bisulfite and sodium metabisulfite? Sodium metabisulfite (Na₂S₂O₅) is a dimer of sodium bisulfite (NaHSO₃). Essentially, two molecules of sodium bisulfite combine to form one molecule of sodium metabisulfite. They both release sulfur dioxide in solution but at differing rates and concentrations.

Search Results:

Sodium Metabisulfite - Introduction, Structure, Preparation and Uses Sodium Metabisulfite has the chemical formula Na2S2O5 and its molecular mass is 190.107g/mol. It is a sulfur-containing ionic compound of sodium. Sodium has a positive charge while …

SODIUM METABISULFITE, SODIUM PYROSULFATE - Water … When in solution, sodium metabisulfite is formed. It has a solubility in water of 54 g/100 ml at 20°C and is avail able at a commercial strength of 97.5-99.0% sodium meta bisulfite. Use: Used to …

Sodium metabisulfite ACS reagent, = 97.0 7681-57-4 Sodium metabisulfite is used in marine shrimp harvesting to prevent the occurrence of black spots. Shrimps are soaked in a sodium metabisulfite solution in ice, which is disposed of in …

Sodium Metabisulphite - PRIME WEST HOLDINGS Chemicals Formula: Na2S205 Tech Grade Sodium Metabisulphite (As SO2), %≥-----64 Fe %≤-----0.005

Protein production for human use from sugarbeet: Byproducts 1 Jan 1993 · Protein extraction Fresh material (15 kg) was chopped, sodium metabi- sulphite solution (12 g/litre Na2S205) was added in a 2:1 ratio to dilute the juice and to avoid oxidation …

Sodium metabisulfite - Wikipedia Sodium metabisulfite or sodium pyrosulfite (IUPAC spelling; Br. E. sodium metabisulphite or sodium pyrosulphite) is an inorganic compound of chemical formula Na 2 S 2 O 5. The …

Sodium metabisulfite analytical standard 7681-57-4 - MilliporeSigma Sodium metabisulfite is primarily used as an antioxidant and antimicrobial agent in a wide variety of foods and drugs. [1] . It is also used as the main additive in the prevention of melanosis in …

Sodium metabisulfite | 7681-57-4 - ChemicalBook 27 Jan 2025 · Sodium metabisulfite (chemical formula: Na2S2O5) appears as a white crystalline or powder solid with a slight sulfur odor. It is toxic upon inhalation and can strongly irritate skin …

Na2S2O5 + H2O = NaHSO3 - Chemical Equation Balancer Balance the reaction of Na2S2O5 + H2O = NaHSO3 using this chemical equation balancer!

Sodium Metabisulfite - Na2S2O5, 7681-57-4 - Kemicalinfo Sodium metabisulfite (Na2S2O5) is a chemical compound used as a preservative and antioxidant in food and beverages. It can also be used as a disinfectant and bleaching agent in various …

Sodium metabisulfite - MilliporeSigma Formation of reactive impurities in aqueous and neat polyethylene glycol 400 and effects of antioxidants and oxidation inducers.

SODIUM METABISULFITE | CAMEO Chemicals | NOAA Noncombustible, but may decompose to emit toxic oxide fumes of sulfur and sodium when heated to high temperature. A corrosive acid when mixed with water. Used as a food preservative and …

Sodium Metabisulfite (Na2S2O5) - Structure, Properties, Uses Sodium metabisulfite is a chemical compound with the formula Na 2 S 2 O 5. It is also known as sodium pyrosulfite and sodium disulfite. Na 2 S 2 O 5 is an ionic compound containing the …

Sodium Metabisulfite | Na2S2O5 | CID 656671 - PubChem Sodium metabisulfite appears as a white crystalline or powder solid with a slight sulfur odor. Toxic by inhalation. Strongly irritates skin and tissue. Noncombustible, but may decompose to emit …

Chemical methods of stable isotope separation - Springer initial 1.5 M aqueous solution Na2S205 was used with 3 moles SO2 in it. II. Low Temperature Rectification 1. Carbon Isotope Separation Low temperature rectification of carbon monoxide …

Na2S205 molar mass - Chemical Portal Molar mass calculator computes molar mass, molecular weight and elemental composition of any given compound.

Purification and characterization of diamine oxidase from Triticum ... 1 May 1996 · Diamine oxidase (DAO; EC 1.4.3.6) from the shoots of wheat seedlings was separated into two fractions; A (Mr 55 × 10 4) and B (Mr 11 × 10 4) by chromatography on …

Sodium metabisulfite - Sodium disulfite, Sodium pyrosulfite Synonyms: Sodium disulfite, Sodium pyrosulfite, Sodium metabisulfite. CAS 7681-57-4. Molecular Weight 190.11. Browse Sodium metabisulfite and related products at MilliporeSigma.

Sodium metabisulfite Request for Quotation - ChemBK white or yellowish crystalline powder with a relative density of 1.4. Unstable, heated to 150 ° C above the decomposition of sulfur dioxide, soluble in water and glycerol, insoluble in ethanol. …