Fire -- Atoms and elements -- States of matter -- Units of measurement -- Chemical bonding -- Chemical structures -- Chemical reactions and equilibria -- Earth -- Formations of the Earth -- Igneous rocks -- Sedimentary rocks -- Metamorphic rocks -- Weathering -- The chemistry of soil -- Water -- The properties of water -- Acids, bases, and the pH scale -- Ions in solution -- Redox chemistry -- Colloids and suspended particles -- Water pollution -- Air -- The structure of the atmosphere -- Evolution and composition of the atmosphere -- Biogeochemical cycles -- Global warming and the greenhouse effect -- The ozone layer -- Air pollution