CAS Number
The CAS Number (CAS = Chemical Abstract Service) is used for identification of chemical substances. It is composed of numbers and dashes, and is structured as follows:
- Sequence of digits with up to 7 digits
- Dash
- Sequence of exactly 2 digits
- Dash
- Check digit
- 67-64-1 Acetone
- 7440-17-7 Rubidium
- 7647-01-0 Hydrochloric acid