Industrial chemicals · Taylor, TXCertificate of Analysis
Sample Certificate of Analysis
Sodium Metabisulfite - Technical Grade
Technical Grade
Sample COA. Contact Alliance Chemical with your lot number to request a lot-specific COA.
- CAS number
- 7681-57-4
- Structure
Structure · PubChem - Grade
- Technical Grade
- Assay specification
- 98.0 – 100.0 %
- Answer summary
Sample specification reference for Sodium Metabisulfite - Technical Grade. Source-record results are reference values, not measurements for your lot.
Last reviewed 2026-07-17 by Andre Taki, Chief Commercial Officer, DOT Hazmat–certified (49 CFR 172.704).
Specifications
| Parameter | Specification | Source reference result | Test Method |
|---|---|---|---|
| Assay (Na2S2O5) | 98.0 – 100.0 % | 98.6 % | — |
| Appearance | Free flowing, white to slightly yellow, fine granular crystal having a characteristic odor of sulfur dioxide | Passes test | — |
| Iron (Fe) | 0.0 – 7.0 ppm | 2.5 ppm | — |
| pH of 5% solution | 3.5 to 4.5 | 4.1 | — |
| Solubility (10 % aqueous solution) | Clear and colourless solution | Passes test | — |
| Sodium sulfite (Na2SO3) | 0.0 – 1.0 % | 0.19 % | — |
| Sulfur dioxide (SO2), available | Min. 64.0% | 66.6% | Iodometric titration (I2 / Na2S2O3) |
| Water insoluble matter | Max. 0.05% | 0.0038% | Gravimetric; 10% solution filtered through tared crucible, dried at 105 C |
| Screen size, through 20 mesh (U.S. Sieve) | Min. 95% | 99.8% | ASTM E11 sieve analysis |
Specification limits and source-record results are reproduced from the current product reference used by the TDS. This sample is not an issued certificate and does not identify a tested lot. Contact Alliance Chemical with the product and lot number for lot-specific documentation.
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