ChemBench: Equation Balancer

Not a lookup table, and not just an answer. ChemBench actually solves the chemistry: coefficients come out of conservation equations, pH comes out of an equilibrium solve, enthalpy comes out of Hess's law — then it shows you the formula with your own numbers in it. Turn the coefficient on H₂ from 1 to 2 and watch both sides of the atom balance bar go green. Mix a stock solution with water to hit a target concentration, and see the liquid shift along the pH scale. Flip, scale and stack known enthalpy cards until they add up to the target reaction. Every level ends with a Reaction Card: the law, the balanced equation, the formula, and your level's real values substituted in. MAIN FEATURES • 60 levels across three subjects: Stoichiometry, Solutions, Gases • Three difficulties per subject: Intro, Core, Brainer • True solving — rational-arithmetic balancing, exact equilibrium pH, ideal gas law, Hess's law composition • Reaction Card after every solve, with your own values • Quick tools always at hand: molar mass, equation balancing, unit conversion — results never limited • Unlimited hints, never a consumable • Reaction Codex: unlock laws as you play • Open bench to set your own problems and solve them • Works fully offline. No ads, no accounts, no tracking PRO — ONE-TIME PURCHASE • All 60 levels, including every Brainer level • Full step-by-step derivation on every Reaction Card • Step-by-step working in the quick tools • Open bench: build, name and save your own setups • Full data panel: per-element balance, every species concentration, the whole titration curve, partial pressures and enthalpy breakdown • Extra themes and an alternate app icon • Future local Pro levels in this app PRIVACY Everything runs on your device. Progress syncs through your own private iCloud. No account, no analytics SDK, no data sent to us. NOTE This is a calculation and reasoning tool, not a lab manual — it contains no experimental procedures. Levels use teaching-simplified models (ideal gases, unit activity coefficients, 25 °C standard state). The in-app "About the model" page lists every assumption. Support · Privacy Policy · Terms of Use are in Settings.