Chemistry

Atoms, molecules, reactions, and the periodic table — the science of matter.

Topics covered:Atomic structurePeriodic tableChemical bondingBalancing equationsStoichiometryAcids & bases

Step-by-Step Example

Work through this example one step at a time — or reveal all steps at once.

Example Problem

Balance the chemical equation: H₂ + O₂ → H₂O

Step 2 — reveal when ready

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