GB1255-2007
Working chemical - Sodium carbonate anhydrous
工作基准试剂 无水碳酸钠
GB 1255-2007 is a current mandatory Chinese national standard for Working chemical - Sodium carbonate anhydrous. It appears in the Electronics compliance cluster with a product safety focus and has an implementation date of Nov 1, 2007.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard applies to working chemical reagents, specifically anhydrous sodium carbonate (Na2CO3), intended for use as a working standard in volumetric analysis (titration). It is strictly applicable to high-purity reagents used for analytical calibration and does not cover general industrial or technical grade sodium carbonate.
Technical requirements
GB 1255-2007 specifies stringent physical and chemical requirements for anhydrous sodium carbonate. The standard mandates an extremely high purity level for the Na2CO3 content, alongside strict limits for ignition loss and clarity. Manufacturers must ensure the mass fraction of the active ingredient falls within an exceptionally narrow tolerance band to qualify as a working基准 (working standard). Furthermore, the standard defines maximum allowable limits for various trace impurities and heavy metals. This includes strict controls on compounds such as chlorides, sulfates, total nitrogen, and phosphates/silicates. Compliance with these trace impurity limits is mandatory to prevent interference during analytical titration. Specific heavy metals and elemental impurities, including magnesium, aluminum, potassium, calcium, iron, and lead, are also heavily regulated under the specifications. The reagent must appear as a white powder and meet specific solubility criteria. Suppliers must verify their product against all these chemical parameters before labeling it as a working grade reagent.
Testing methods
The standard outlines rigorous testing procedures, primarily utilizing gravimetric titration for the assay of Na2CO3 content, referencing the general rules specified in GB 10738. Accurate content determination requires precise weighing and titration using a hydrochloric acid standard solution. For impurity assessment, the standard mandates various spectrophotometric and turbidimetric methods. Flame atomic absorption spectrometry (FAAS), following GB/T 9723-1988, is specified for the determination of magnesium, potassium, and calcium. Visual comparison methods against standard colorimetric or turbidimetric solutions are required for testing chlorides, sulfates, iron, and heavy metals.
FAQs
What products are regulated under GB 1255-2007?
This standard regulates working chemical reagents, specifically anhydrous sodium carbonate (Na2CO3) used as a working standard in volumetric analysis. It is not applicable to general industrial or commercial grade sodium carbonate.
Are there any updates from the previous version of GB 1255-2007?
Compared to the previous version, the standard's name was updated to Working chemical-Sodium carbonate anhydrous, and the determination method for the Na2CO3 content was modified. Manufacturers previously certified under the 1990 version must update their testing protocols to comply with the new titration requirements.
How does GB 1255-2007 differ from ISO standards?
While GB 1255-2007 references several ISO standards for general test methods (such as ISO 6353-1:1982 for impurities), it establishes specific Chinese national limits and a unique gravimetric titration method for content determination. Compliance with ISO standards alone does not guarantee compliance with this GB standard.
The summary above provides a high-level overview of GB 1255-2007. To ensure complete compliance for your chemical products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 1255-2007 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Product
- CCS
- G61
- ICS
- 71.040.30
- Competent department
- Ministry of Industry and Information Technology
- Technical committee
- Ministry of Industry and Information Technology
Relationships
Replaces:GB 1255-1990