Common Chemistry is a resource from Chemical Abstracts Service (CAS) which allows one to search for chemical information using a variety of search terms, whether the terms be common names (aspirin, table salt), basic chemical names (acetylsalicylic acid, sodium chloride), or even the official CAS registration number (50-78-2, 7647-14-5).
Although this does not search the entire CAS database, it is an excellent starting point for most of the chemical information questions posed students and the general public.
Note the link to the Wikipedia entry (just above the disclaimer) for many, but not all, results; not many “authoritative” resources are confident enough in their users to connect them with resources developed and maintained by the crowd.
found via ResourceShelf
