General chemistry

Everyday lab math — molarity, dilutions, molar mass, buffers, and serial dilutions. The bench toolkit every chemist reaches for daily.

7 guides 9 calculators 7 cheat sheets

Reading path

Start here. Each guide is a self-contained tutorial with worked examples and cited sources.

  1. Stoichiometry: how to think in moles The mole map, limiting reagents, and the cascading errors that ruin a synthesis calc — with three worked problems. 10 min
  2. Limiting reagent, deeply It is not the smallest number of moles — it is the reagent that runs out first at the reaction ratio. The three-column method that never fails. 9 min
  3. Percent yield accounting: where the mass went Theoretical yield is a ceiling, actual yield is the receipt, and the gap between them is where the chemistry actually happened. 10 min
  4. Concentrations decoded: mass %, molality, ppm Molarity is one of six ways to say 'how concentrated'. Mass percent, molality, ppm, mole fraction — each has a job. 10 min
  5. The ideal gas law: PV=nRT and where it breaks Four variables, one line — until temperature drops or pressure climbs. Boyle, Charles, Avogadro, and the van der Waals correction that patches the damage. 11 min
  6. Balancing redox equations: the half-reaction method Split the equation in two, balance atoms, balance charge with electrons, add. A seven-step algorithm that never fails, in acid or in base. 11 min
  7. Colligative properties: the four that matter Vapour-pressure lowering, boiling-point elevation, freezing-point depression, osmotic pressure — four properties, one common cause: lowered solvent chemical potential. 11 min

Calculators

Cheat sheets