Online Science Tools
Free chemistry and math calculators for coursework — chemical equilibrium, pH, stoichiometry, equation balancing, buffers, graphing, phase portraits, and short study guides. No account required.
Chemistry
Reactions & stoichiometry
5- Equation BalancerBalance chemical equations and inspect stoichiometric coefficients on both sides.
- StoichiometryCalculate molar mass and convert between moles, grams, and particles for chemical formulas.
- Reaction StoichiometryFind limiting reagents and theoretical yields from balanced equations and starting amounts.
- Composition / EmpiricalGet mass percent composition from a formula, or find empirical and molecular formulas from percent data.
- Redox BalancerBalance redox equations in acidic or basic medium with atom and charge conservation (H₂O / H⁺ / OH⁻).
Solutions & concentration
2Equilibrium & acids
4- EquilibriumChemical equilibrium calculator for Kc/Kp, reaction quotient Q, ICE tables, and equilibrium concentrations.
- pH CalculatorpH and pOH calculator for strong/weak acids and bases—including ammonia with Kb = 1.8×10⁻⁵—and simple buffers (Henderson–Hasselbalch).
- Buffer RecipePrepare named buffers (phosphate, acetate, Tris, and more) from target pH, total concentration, and volume using Henderson–Hasselbalch.
- Ksp / SolubilityConvert between Ksp and molar solubility, and compare ion product Q with Ksp for precipitation.
Energy, rates & electrochemistry
3- ThermochemistryCompute ΔH° from formation enthalpies, apply Hess’s law, run calorimetry q = mcΔT, and scale heat with moles.
- KineticsUse zero-, first-, and second-order integrated rate laws to find concentration, time, k, or half-life.
- Nernst EquationCalculate non-standard cell potential E from E°, n, and Q, plus ΔG = −nFE.
Mathematics
Graphing & dynamics
3Computing
Guides
2