Chem1 Virtual Textbook An Intro to Chemistry - Mark Bishop
Concept Development Studies in Chemistry Chemistry of the Main Group Elements
Boundless Chemistry General Chemistry - Principles, Patterns and Applications
Introductory Chemistry Online UC Davis ChemWiki

Try out several of these texts for different topics and use the ones that best fit your learning style. If you find a particularly good chapter, post a note for your classmates on ChemGroups.