Chemical numbering schemes

Chemical numbering schemes refer to systematic methods used to identify and organize the unique arrangement of atoms and functional groups in a chemical compound, as well as to provide a clear and unambiguous way to refer to each component of a compound or molecules.

UN numbers, or United Nations numbers, are four-digit numeric codes assigned by the United Nations to identify hazardous substances and articles, primarily for the purpose of international transport. These numbers are part of the UN's transportation regulations and are used by various organizations, including the International Air Transport Association (IATA) and the International Maritime Organization (IMO), to facilitate the safe transportation of dangerous goods. The list of UN numbers includes a wide variety of substances, including: - Flammable liquids (e.g.

The Beilstein Registry Number (BRN) is a unique identifier assigned to chemical substances in the Beilstein database, which is a comprehensive repository of organic chemistry information. This database includes data on chemical structures, properties, reactions, and other relevant information. BRNs are useful for chemists and researchers as they provide a systematic way to reference substances, ensuring clarity and avoiding confusion between compounds with similar names or structures.

A CAS Registry Number (CAS RN or CAS Number) is a unique numerical identifier assigned to a specific chemical substance by the Chemical Abstracts Service (CAS), a division of the American Chemical Society. These numbers are used to provide a way to identify chemical compounds, mixtures, and other substances in a standardized format.

An E number is a code used in the European Union to identify food additives that have been assessed for safety and authorized for use in food products. These numbers typically start with the letter "E" followed by a number, and they cover a wide range of substances such as preservatives, colorings, flavor enhancers, emulsifiers, and stabilizers. For example: - E100 is curcumin (a coloring agent). - E200 is sorbic acid (a preservative).

The term "European Community number" could refer to various identifiers depending on context, but it is most commonly associated with the "European Community (EC) Number" used in the context of chemical substances and regulatory compliance. The EC number is a numerical identifier assigned to substances registered under the European Union's regulation of chemicals, particularly under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) directive.

The European List of Notified Chemical Substances, often referred to as the European Inventory of Existing Commercial Chemical Substances (EINECS), is a registry of chemical substances that were commercially available in the European Union before the introduction of the REACH regulation in June 2007. EINECS includes details about these substances, such as their names, identification numbers, and potential safety assessments.

The Harmonized System (HS) is an internationally standardized system of names and numbers for classifying traded products. It is developed and maintained by the World Customs Organization (WCO) and is used by countries around the world for tariff classification, trade statistics, and the collection of duties and taxes.

The Kabat numbering scheme is a method used to systematically number the amino acids in the variable regions of immunoglobulins (antibodies) and T-cell receptors. This scheme is primarily used in the fields of immunology and molecular biology to identify and describe the structures of antibodies and their variable regions, which are crucial for recognizing and binding to antigens.

TARIC stands for "Tarif Intégré de la Communauté" (Integrated Tariff of the Community) and is a comprehensive database of all customs and trade regulations for the European Union (EU). The TARIC code is an alphanumeric code that is used to classify goods for customs purposes when they are imported into or exported from the EU. The TARIC system provides information on duty rates, applicable regulations, restrictions, and any trade measures that may apply to specific products.

The UN number, or United Nations number, is a four-digit code assigned to hazardous materials and substances for identification purposes during transportation. These numbers are part of the UN's system for classifying and labeling dangerous goods, which facilitates safe handling and transport by providing essential information about the risks associated with the materials. Each UN number corresponds to a specific substance or group of substances, making it easier for shippers, carriers, and regulatory authorities to recognize and manage hazardous materials in compliance with international standards.