# Chemistry calculators

> Molar mass, moles, molarity, dilution, ideal gas law, pH, half-life, percent yield.

10 calculators. HTML index: https://tttkmbb.com/chemistry · JSON: https://tttkmbb.com/api/v1/calculators?category=chemistry

- [Molar Mass Calculator](https://tttkmbb.com/chemistry/molar-mass.md): Parses a chemical formula (including brackets, nested groups and hydrates) and sums IUPAC 2021 standard atomic weights to give the molar mass in g/mol, plus the atom count and mass-percent composition of each element. Tool: `calculate_molar_mass`.
- [Moles to Grams Calculator](https://tttkmbb.com/chemistry/moles-mass.md): Converts between mass in grams and amount in moles using the molar mass (from a formula or given directly), and reports the number of molecules or formula units from the Avogadro constant. Any two of molar mass, mass and moles give the third. Tool: `convert_moles_and_mass`.
- [Molarity Calculator](https://tttkmbb.com/chemistry/molarity.md): Computes molar concentration (mol/L) of a solution from the amount of solute (moles, or mass with a formula or molar mass) and the solution volume, or the moles and mass of solute needed to prepare a target molarity. Tool: `calculate_molarity`.
- [Dilution Calculator](https://tttkmbb.com/chemistry/dilution.md): Applies the dilution equation C1·V1 = C2·V2 to find the missing one of stock concentration, stock volume, final concentration or final volume, plus the solvent to add and the dilution factor. Tool: `calculate_dilution`.
- [Ideal Gas Law Calculator](https://tttkmbb.com/chemistry/ideal-gas-law.md): Solves the ideal gas equation PV = nRT for whichever of pressure, volume, amount or temperature is left empty, with pressure in atm, kPa, bar, mmHg or psi and temperature in °C, K or °F. Tool: `solve_ideal_gas_law`.
- [pH Calculator](https://tttkmbb.com/chemistry/ph.md): Converts between pH, pOH, hydrogen-ion concentration and hydroxide-ion concentration at 25 °C (Kw = 1.0×10⁻¹⁴) from any one of them, and classifies the solution as acidic, neutral or basic. Tool: `calculate_ph`.
- [Half-Life Calculator](https://tttkmbb.com/chemistry/half-life.md): Computes first-order exponential decay: given two of half-life, elapsed time and remaining amount (with an initial amount) it solves the third and reports the remaining fraction, number of half-lives, decay constant and mean lifetime. Tool: `calculate_half_life_decay`.
- [Percent Yield Calculator](https://tttkmbb.com/chemistry/percent-yield.md): Divides the actual (experimental) yield by the theoretical yield to give percent yield, plus the amount and percentage of product lost. Tool: `calculate_percent_yield`.
- [Mass Percent Calculator](https://tttkmbb.com/chemistry/mass-percent.md): Computes the mass percent (% w/w) of a solute from the solute mass and either the total solution mass or the solvent mass, and expresses the same concentration as mass fraction, parts per million and parts per billion. Tool: `calculate_mass_percent`.
- [Henderson–Hasselbalch Calculator](https://tttkmbb.com/chemistry/henderson-hasselbalch.md): Computes the pH of a buffer from the acid's pKa and the concentrations (or ratio) of conjugate base and weak acid with the Henderson–Hasselbalch equation, or the base/acid ratio required for a target pH. Tool: `calculate_henderson_hasselbalch_ph`.