This list includes different tools to help you locate information in chemistry.
There is one encyclopedia source:
There are journal article databases with structure and reaction search tools:
Scifinder Scholar, Reaxys, PubMed, and Chemspider
There are three tools to search for journal article citations:
Web of Science, Scifinder, and Google Scholar
Note: Scifinder Scholar requires registration.
Please email email@example.com for the URL.
There are lots of classroom materials of chemistry lectures, problem sets and exams on the web:
The video below is from one of the many collections from the Royal Institution's RI Channel in the UK.
Khan Academy has many introductory chemistry lecture videos. Note that problem set solutions may be locked.
CrashCourse has videos on Chemistry course topics.
MIT OpenCourseWare has lectures, problem sets and exams online.
UCI Open has lectures, problems and solutions in individual lectures.
Periodic Table of Videos covers many chemical topics.
Alternative Periodic Tables you may not have seen.
Periodic Table parodies on a variety of themes.