Contents
How do I find my CAS Number for chemicals?
To find the CAS number of a compound given its name, formula or structure, the following free resources can be used:
- NLM,NIH ChemIDplus.
- NIST Chemistry WebBook.
- NCI/CADD Chemical Identifier Resolver.
- ChemSub Online (Multilingual chemical names)
- NIOSH Pocket Guide to Chemical Hazards, index of CAS numbers.
What do the numbers in chemical names mean?
The small number behind each element symbol designates the number of atoms of each element in a chemical formula. If there is no number, it is assumed there is only one of those elements. A large number in front of a compound designates how many units there are of that compound.
What is a chemical product number?
A Product Identifier is defined in paragraph C of 29 CFR 1910.1200, the OSHA Hazard Communication Standard (HCS), as the name or number used for a hazardous chemical on a label or in the SDS. It provides a unique means by which the user can identify the chemical.
What is CAS Number in chemicals?
A CAS Number is a numerical designation for chemicals that is maintained by the Chemical Abstracts Service (CAS) of the American Chemical Society. Each number assigned by the CAS is unique to one chemical substance. There is no correlation to that scientific chemical number for the substance.
Can a chemical have two CAS numbers?
A chemical may also be listed with multiple CAS numbers when multiple numbers have been inadvertently assigned to the same chemical. This multiple assignment can occur when forms of a chemical are originally believed to be unique, but after further review by chemists, are identified as the same chemical.
Does every chemical have a CAS Number?
Every chemical is assigned a CAS Number.
How do you read chemical names?
When naming molecular compounds prefixes are used to dictate the number of a given element present in the compound. ” mono-” indicates one, “di-” indicates two, “tri-” is three, “tetra-” is four, “penta-” is five, and “hexa-” is six, “hepta-” is seven, “octo-” is eight, “nona-” is nine, and “deca” is ten.
What are the three types of chemical formulas?
There are three main types of chemical formulas: empirical, molecular and structural. Empirical formulas show the simplest whole-number ratio of atoms in a compound, molecular formulas show the number of each type of atom in a molecule, and structural formulas show how the atoms in a molecule are bonded to each other.
What is a product identifier for chemicals?
Product Identifier is how the hazardous chemical is identified. This can be (but is not limited to) the chemical name, code number or batch number. The manufacturer, importer or distributor can decide the appropriate product identifier. The same product identifier must be both on the label and in section 1 of the SDS.
What does a CAS Number look like?
A CAS Registry Number is a numeric identifier that can contain up to 10 digits, divided by hyphens into three parts. The right-most digit is a check digit used to verify the validity and uniqueness of the entire number. For example, 58-08-2 is the CAS Registry Number for caffeine.
How is CAS Number used?
CAS Numbers are up to 10 digits long using the format xxxxxxx-yy-z. They are assigned to a compound as the CAS registers a new compound. The number has no significance to the chemistry, structure, or chemical nature of the molecule. The CAS Number of a compound is a useful way to identify a chemical over its name.