Chemistry Calculators

Activity Series Calculator

Predict whether a single displacement reaction will occur by comparing metal positions in the electrochemical activity series. Shows the reaction equation when displacement is possible.

Chemical Equation Balancer

Balance any chemical equation using matrix null-space methods. Enter reactants and products separated by + and =, and get the smallest integer coefficients.

Chemical Formula Calculator

Find the molar mass and elemental composition of any chemical formula. Enter formulas like H2O, C6H12O6, or Ca(OH)2 and get mass and percent composition.

Collision Theory Calculator

Calculate reaction rate using collision theory. Enter collision frequency, steric factor, and activation energy to find what fraction of collisions produce a reaction at a given temperature.

Combustion Stoichiometry Calculator

Balance combustion equations for any hydrocarbon CnHm. Calculates O2 required, CO2 and H2O produced, stoichiometric air-fuel ratio, and percent excess air.

Flash Point Estimator

Estimate the flash point of an organic liquid from its normal boiling point using the Satyanarayana-Rao correlation. Also classifies the flammability hazard category.

Formal Charge Calculator

Calculate formal charge for up to 3 atoms using FC = V - L - B/2. Checks whether the Lewis structure sum matches the molecular charge and flags the most stable arrangement.

Hybridization Calculator

Determine orbital hybridization from bonding pairs and lone pairs. Enter the electron domain count to get the hybridization type and electron geometry.

Hydrogen Bonding Calculator

Estimate the maximum number of hydrogen bonds a molecule can form. Enter donor H atoms (bonded to N/O/F) and acceptor lone pairs to get bonding capacity.

Le Chatelier's Principle Calculator

Predict equilibrium shift direction when concentration, temperature, or pressure changes. Applies Le Chatelier's Principle to reversible reactions with step-by-step reasoning.

Lewis Structure Electron Calculator

Count valence electrons, bonding pairs, and lone pairs for a simple molecule. Enter the central atom and surrounding atoms to see the electron accounting.

Orbital / Electron Configuration Calculator

Look up the electron configuration for any element from hydrogen to xenon. Get full spdf notation, noble gas shorthand, and subshell filling order.

Quantum Number Calculator

Validate quantum numbers n, l, ml, and ms for an electron. Determines the orbital type, subshell capacity, electron spin state, and whether the combination is physically allowed.

Reaction Kinetics Calculator — Integrated Rate Laws

Calculate concentration vs time for zero, first, and second order reactions. Find half-life, time to reach a target concentration, and remaining amount at any time t.

Redox Reaction Calculator

Calculate cell potential, Gibbs free energy change, and equilibrium constant for a redox cell. Enter standard reduction potentials for the cathode and anode.

Resonance Structures Formal Charge Calculator

Calculate formal charges on each atom of a Lewis structure to compare resonance structures. Enter element, bonds, and lone pairs to get the formal charge.

Salt Chemistry Calculator — pH and Classification

Classify a salt as acidic, basic, or neutral based on its parent acid and base. Estimates pH of a salt solution using Kb of conjugate base or Ka of conjugate acid.

VSEPR Calculator

Predict molecular geometry using VSEPR theory. Enter the bonding domains and lone pairs to get the molecular shape, bond angle, and AXnEm notation.

Water Hardness Calculator and Unit Converter

Convert water hardness between ppm (mg/L), grains per gallon, German degrees (dGH), and mmol/L. Includes WHO soft, moderate, hard, and very hard classification scale.

Atom Economy Calculator

Calculate the atom economy of a chemical reaction. Enter the molecular weight of the desired product and all byproducts to see how efficiently atoms are used.

Degree of Unsaturation Calculator

Calculate degree of unsaturation for any organic molecule. Enter carbon, hydrogen, nitrogen, and halogen counts to find rings and double bond equivalents.

Electrochemical Cell Potential Calculator

Calculate standard cell potential from cathode and anode electrode values. Enter E° for each half-cell to find total voltage, Gibbs free energy, and spontaneity.

Elemental Analysis Calculator

Calculate the molecular weight and mass percent composition of a compound. Select up to four elements with their atom counts to get results.

Gas Density Calculator

Calculate gas density at any temperature and pressure. Enter the molar mass, pressure, and temperature to find density in g/L using the ideal gas law.

Ionic Strength Calculator

Calculate the ionic strength of a solution from ion concentrations and charges. Enter up to four ion species to find the overall ionic strength.

pOH Calculator

Calculate pOH, pH, and hydroxide ion concentration for any solution. Enter an OH concentration or pH value to find all related quantities at 25 degrees C.

Thermochemistry Calculator

Calculate heat absorbed or released using q = mcΔT. Select a substance from a list of specific heat capacities and enter mass and temperature change.

Valence Electrons Calculator

Find the number of valence electrons for any main-group element. Select an element from the periodic table to see its valence electron count and bonding behavior.

Henderson-Hasselbalch Calculator

Calculate buffer pH from pKa and the ratio of conjugate base to weak acid using the Henderson-Hasselbalch equation. Includes titration curve.

Mole Fraction Calculator

Calculate mole fractions of up to four components from moles or from masses with molar masses. Used for solution concentration and gas mixtures.

Antoine Vapor Pressure Calculator

Calculate vapor pressure of common liquids at any temperature using the Antoine equation. Covers water, ethanol, methanol, acetone, benzene, and toluene.

Beer-Lambert Law Absorbance Calculator

Calculate absorbance, concentration, or path length using the Beer-Lambert Law (A = elc). Convert between transmittance and absorbance for spectrophotometry.

Crystal Lattice Density Calculator

Calculate theoretical crystal density from unit cell parameters. Find density for cubic and other crystal systems from lattice constants and molecular weight.

Electronegativity and Bond Type Calculator

Determine bond type from electronegativity difference. Identifies ionic, polar covalent, and nonpolar covalent bonds using the Pauling scale for 50+ elements.

ICE Table Equilibrium Calculator

Solve weak acid and weak base equilibrium using the ICE table method. Calculate pH, percent ionization, and equilibrium concentrations from Ka or Kb.

Isoelectric Point (pI) Calculator

Calculate the isoelectric point (pI) of amino acids from pKa values. Includes a preset dropdown for all 20 standard amino acids with pre-filled pKa values.

Ka and pH Calculator (Acid Dissociation)

Calculate Ka from pH and concentration, pH from Ka, or buffer pH using Henderson-Hasselbalch. Includes ICE table, percent ionization, and weak acid Ka table.

Mass Percent Calculator

Calculate the mass percent (weight percent) of a solute in a solution, plus mole fraction and parts per million (ppm) conversions.

Oxidation State Calculator

Determine oxidation states (oxidation numbers) for elements in compounds and ions. Apply oxidation number rules step by step for any ionic or molecular formula.

Percent Ionization Calculator

Calculate percent ionization of weak acids or bases from Ka or Kb and initial concentration. Shows ICE table setup and Ostwald's dilution law with examples.

PPM / PPB Concentration Converter

Convert between parts per million (ppm), parts per billion (ppb), parts per trillion (ppt), percentage (%), and mg/L for water quality and chemistry.

Acid-Base Neutralization Calculator

Calculate the volume or concentration needed to neutralize an acid or base. Supports HCl, H₂SO₄, H₃PO₄, NaOH, Ca(OH)₂, and custom compounds.

Activation Energy from Two Rate Constants

Calculate activation energy Ea using two rate constants at two temperatures. Uses the Arrhenius equation in linear form. Classify reaction barrier.

Buffer Capacity Calculator

Calculate the buffer capacity β — how much strong acid or base a buffer can absorb per pH unit change. Maximum capacity occurs at pH = pKa.

Calorimetry Heat Transfer Calculator

Calculate heat absorbed or released using q = mcΔT. Supports coffee-cup calorimetry for reactions. Includes common specific heat values.

Chromatography Rf Calculator

Calculate the retention factor Rf from spot and solvent front distances in TLC or paper chromatography. Identify compounds and assess separation quality.

Clausius-Clapeyron Vapor Pressure Calculator

Calculate vapor pressure at a new temperature using the Clausius-Clapeyron equation. Find how vapor pressure changes with temperature for any liquid.

Concentration Cell Voltage Calculator

Calculate the voltage of a concentration cell — two identical electrodes with different ion concentrations. Voltage approaches zero as concentrations equalize.

Degree of Ionization of Weak Acid/Base

Calculate the degree of ionization (α) of a weak acid or base from Ka/Kb and initial concentration. Includes equilibrium concentrations and pH.

Dilution Factor and Serial Dilution Calculator

Calculate C₁V₁ = C₂V₂ for single dilutions. Also calculate serial dilutions showing concentration at each step. Essential for lab prep and microbiology.

Dipole Moment Calculator

Calculate the electric dipole moment from charge separation distance. Convert between Debye and SI units. Understand polarity and molecular geometry effects.

Electrochemical Cell Voltage Calculator

Calculate standard cell voltage E°cell from half-reaction reduction potentials. Find ΔG° and the equilibrium constant K for the cell reaction.

Empirical Formula Calculator

Calculate the empirical formula from percent composition data. Enter up to 5 elements with their mass percentages and get the simplest whole-number ratio.

Enthalpy of Solution / Dissolution Calculator

Calculate the heat released or absorbed when a solute dissolves in water. Find the temperature change in a coffee-cup calorimeter setup.

Entropy Change Calculator

Calculate entropy change for heat transfer, isothermal gas expansion, or temperature change processes. Includes universe entropy check.

Equilibrium Constant (Keq) Calculator

Calculate Keq from equilibrium concentrations for reactions with up to 2 reactants and 2 products. Includes Kp conversion for gas-phase reactions.

Faraday's Law of Electrolysis Calculator

Calculate the mass deposited or dissolved during electrolysis. Enter current, time, and electrode material. Supports copper, aluminum, silver, gold, and more.

First-Order Reaction Half-Life Calculator

Calculate the half-life and concentration over time for 0th, 1st, and 2nd order chemical reactions. Find time to reach any percentage of original concentration.

Freezing Point Depression Calculator

Calculate the freezing point depression ΔTf = Kf × m × i. Find the new freezing point of solutions. Useful for antifreeze, road salt, and osmometry.

Gas Compressibility Factor (Z) Calculator

Calculate the compressibility factor Z = PV/nRT for real gases using the van der Waals equation. Compare real vs ideal gas behavior.

Gas Molecule Speed Calculator

Calculate the rms speed, average speed, and most probable speed of gas molecules at any temperature. Based on the Maxwell-Boltzmann distribution.

Gibbs Free Energy Calculator

Calculate Gibbs free energy ΔG = ΔH - TΔS. Determine spontaneity, crossover temperature, and equilibrium relationship. Essential for thermochemistry.

Graham's Law of Effusion Calculator

Calculate relative effusion rates of two gases using Graham's Law. Find how much faster lighter gases escape through a small opening.

Heat of Combustion Calculator

Calculate the heat released when burning fuels. Choose from methane, ethanol, propane, octane, hydrogen, or enter a custom combustion enthalpy.

Henry's Law Gas Solubility Calculator

Calculate gas solubility in liquid using Henry's Law C = KH × P. Find dissolved gas concentration for O2, CO2, N2, and more at different pressures.

Lattice Energy Estimator (Kapustinskii Equation)

Estimate ionic lattice energy using the Kapustinskii equation. Enter ion charges, ionic radii, and coordination number to calculate lattice energy in kJ/mol.

Mean Free Path of Gas Molecules

Calculate the mean free path and collision frequency of gas molecules from temperature, pressure, and molecular diameter. Based on kinetic molecular theory.

Molality Calculator

Calculate molality (mol solute per kg solvent) and mole fraction. Convert between molality and molarity using solution density for colligative properties.

Nernst Equation Calculator

Calculate cell potential at non-standard conditions using the Nernst equation E = E0-(RT/nF)*lnQ. Enter standard potential, electron count, Q, and temperature.

Normality and Equivalents Calculator

Calculate normality, equivalents, and equivalent weight for acids, bases, and redox reagents. Includes N₁V₁ = N₂V₂ for volumetric analysis.

Osmolarity Calculator

Calculate osmolarity from solute concentrations and Van t Hoff factors. Supports up to 4 solutes. Compare to plasma osmolarity and understand osmotic pressure.

Partition Coefficient (Log P) Calculator

Calculate partition coefficient P and log P between two immiscible phases. Find extraction efficiency and number of extractions needed for complete separation.

Percent Composition by Mass Calculator

Calculate the percent composition by mass of each element in a compound. Enter up to 6 elements and get molar mass, percentages, and empirical formula hint.

Percent Yield Calculator

Calculate the percent yield of a chemical reaction from actual and theoretical yields. Understand why reactions never give 100% yield.

Rate Law and Reaction Rate Calculator

Calculate reaction rate using rate = k[A]^m[B]^n. Find how doubling a concentration affects rate for 0th, 1st, and 2nd order reactions.

Reaction Enthalpy Calculator (Hess's Law)

Calculate standard enthalpy of reaction using formation enthalpies (Hess's law) or bond energies. Determine if a reaction is exothermic or endothermic.

Reaction Quotient (Q) vs Keq Calculator

Calculate the reaction quotient Q and compare it to Keq to predict which direction a reaction will proceed. Uses up to 2 reactants and 2 products.

Solubility Product (Ksp) Calculator

Calculate Ksp from molar solubility, or find molar solubility from Ksp. Supports ionic compounds with presets for AgCl, BaSO4, CaF2, and more.

Van't Hoff Factor Calculator

Calculate the van't Hoff factor from freezing point depression or degree of dissociation. See how electrolytes affect boiling point and osmotic pressure.

Vapor Pressure Calculator (Raoult's Law)

Calculate vapor pressures in ideal liquid mixtures using Raoult's Law. Find total and partial pressures, vapor composition, and when ideal behavior applies.

Vapor Pressure Lowering Calculator

Calculate vapor pressure lowering when a non-volatile solute dissolves. Uses Raoult's Law for colligative properties. Find mole fraction and new vapor pressure.

Acid-Base Titration Calculator

Calculate concentration, volume, or moles of acid or base in a titration. Solve for unknown concentration using the titration equation and equivalence point.

Arrhenius Reaction Rate Calculator

Calculate reaction rate constants using the Arrhenius equation. Find how temperature affects speed and determine activation energy from two rate measurements.

Buffer Solution pH Calculator (Henderson-Hasselbalch)

Calculate the pH of a buffer solution using the Henderson-Hasselbalch equation. Enter the acid pKa and concentrations of the conjugate base and weak acid.

Limiting Reagent Calculator

Find the limiting reagent in a chemical reaction. Calculate theoretical yield, percent yield, and the amount of excess reagent remaining after the reaction.

Moles to Grams Converter (Chemistry)

Convert between moles, grams, and number of particles for any element or compound. Enter the molar mass to perform stoichiometry conversions instantly.

Osmotic Pressure Calculator

Calculate osmotic pressure using the van't Hoff equation. Enter molarity, van't Hoff factor, and temperature to get pressure in atm, kPa, mmHg, or bar.

Molar Concentration Calculator

Calculate molarity (mol/L), moles, solute mass, or solution volume — solve for any variable in the molarity formula with unit conversions and worked examples.

Stoichiometry Calculator

Calculate moles and mass of reactants and products from a balanced equation. Identifies limiting reagent, theoretical yield, and percent yield.

Boiling Point Elevation Calculator

Calculate how much the boiling point of a liquid increases when a solute is dissolved. Uses the colligative property formula ΔTb = Kb × m.

Charles's Law Gas Temperature and Volume Calculator

Calculate gas volume or temperature changes using Charles's Law. Find the new volume or temperature of a gas at constant pressure.

Chemical Molar Mass Calculator

Calculate the molar mass of common chemical compounds. Enter element symbols and counts to get the molecular weight in g/mol.

Combined Gas Law Calculator

Solve for pressure, volume, or temperature using the combined gas law (P₁V₁/T₁ = P₂V₂/T₂). Supports metric and imperial units.

Ideal Gas Law Calculator (PV=nRT)

Solve the ideal gas law equation PV=nRT for any unknown variable. Calculate pressure, volume, moles, or temperature of an ideal gas.

pH Mixing Calculator

Calculate the resulting pH when mixing two solutions of different pH and volume. Covers acid-acid, base-base, and acid-base mixing.

Chemical Solution Mixer

Calculate how to dilute a stock solution using C₁V₁ = C₂V₂. Enter any three values to find the fourth — for chemistry labs, cleaning products, and medical prep.

pH Dilution Calculator

Calculate new pH after diluting an acid or base from initial pH, volume, and water added. Uses C1V1 = C2V2 converted to hydrogen ion concentration.

Gas Pressure at Depth Calculator

Calculate absolute and gauge pressure at any depth using P = ρgh + P_atm. Returns pressure in PSI, bar, atm, and kPa for scuba and hydraulic engineering.

Boyle's Law Calculator

Solve Boyle's Law P1V1 = P2V2 for any unknown variable. Enter any three of the four values — initial pressure, volume, final pressure, or final volume.

Dilution Calculator

Calculate chemical dilutions using the C1V1 = C2V2 formula. Solve for any unknown concentration or volume for lab solution preparation in mL, L, and mM.

Ideal Gas Law Calculator

Calculate pressure, volume, moles, or temperature using PV = nRT (R = 8.314 J/mol·K). Solves for any one unknown from the three others in Pa, atm, and liters.

pH Calculator

Calculate pH from hydrogen ion concentration or find H+ concentration from pH. Shows whether a solution is acidic, basic, or neutral.