Introductory chemistry
Watch a intro video2 resources
⬡ Website
Video series
Problem sets & exercises
Chemistry - Khan Academy
Full introductory chemistry with videos and built-in practice - atomic structure bonding stoichiometry acids/bases kinetics and thermodynamics. The go-to self-paced resource.
▶ YouTube
Video series
Crash Course Chemistry
46 punchy 10-minute episodes covering all of introductory chemistry - atoms bonding reactions equilibrium thermodynamics and electrochemistry. Hank Green at his most entertaining.