Chemistry Calculators

Calculate activation energy, rate constant, or temperature using the Arrhenius equation: k = A·exp(-Ea/RT).

Calculate rate constants, activation energy, or temperature using the Arrhenius equation k = Ae^(-Ea/RT). Supports single-point and two-point calculations.

Convert between moles, particles, and grams using Avogadro's number (6.022 × 10²³).

Calculate absorbance, concentration, molar absorptivity, or path length using the Beer-Lambert law: A = εbc. Also computes transmittance.

Calculate how much bleach to add to water for a desired sodium hypochlorite concentration. Supports household and industrial bleach strengths.

Calculate the boiling point elevation of a solution using ΔTb = i × Kb × m. Supports water, ethanol, benzene, and custom solvents.

Calculate pressure or volume changes using Boyle's Law (P₁V₁ = P₂V₂) for gases at constant temperature.

Calculate the pH of a buffer solution using the Henderson-Hasselbalch equation: pH = pKa + log([A⁻]/[HA]).

Calculate heat absorbed or released using q = mcΔT. Supports common substances with preset specific heat values.

Calculate volume or temperature changes using Charles's Law (V₁/T₁ = V₂/T₂) for gases at constant pressure.

Calculate boiling point elevation, freezing point depression, and vapor pressure lowering for solutions.

Determine the empirical formula of an organic compound from combustion analysis data (CO₂ and H₂O produced).

Convert between concentration units: molarity, mass percent, ppm, ppb, and mg/L. Uses molecular weight and solution density for accurate conversions.

Calculate total pressure or partial pressures of gas mixtures using Dalton's Law of Partial Pressures.

Calculate dilution using the C1V1 = C2V2 equation. Solve for any of the four variables.

Calculate the standard cell potential from half-cell reduction potentials: E°_cell = E°_cathode - E°_anode.

Determine the empirical formula of a compound from percent composition or mass data of its elements.

Calculate the heat of reaction (q = mcΔT), enthalpy change, or calorimetry results for chemical reactions.

Calculate entropy change (ΔS) for phase changes, temperature changes, and ideal mixing. Assess spontaneity using the second law of thermodynamics.

Calculate Kc, Kp, or convert between them. Find equilibrium constants from concentrations or pressures, and compute ΔG°.

Calculate the freezing point depression of a solution using ΔTf = i × Kf × m. Supports water, benzene, cyclohexane, and custom solvents.

Calculate the volume of a gas at STP or any temperature and pressure using the ideal gas law (PV = nRT).

Calculate Gibbs free energy using ΔG = ΔH - TΔS to determine reaction spontaneity.

Calculate remaining quantity, elapsed time, or half-life for radioactive decay using N = N₀ × (1/2)^(t/t½).

Calculate buffer pH using the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]). Determine pH from pKa and conjugate acid/base concentrations.

Calculate gas solubility in liquids using Henry's Law: C = k_H × P, where C is concentration and P is partial pressure.

Calculate pressure, volume, moles, or temperature using the ideal gas law PV = nRT.

Calculate individual ion concentrations and ionic strength from dissolved salts in solution.