Chemistry
Molar mass, molarity, pH, gas laws & stoichiometry
Molar Mass / Molecular Weight
Parse a chemical formula (e.g. H2O, C6H12O6, CuSO4·5H2O) and compute the molar mass.
Molarity (M)
Calculate molarity = moles of solute ÷ liters of solution.
Molality (m)
Calculate molality = moles of solute ÷ kg of solvent.
Moles Calculator
Calculate moles = mass ÷ molar mass.
pH Calculator
Calculate pH from [H⁺] or vice versa.
Dilution Calculator (C₁V₁ = C₂V₂)
Solve C₁V₁ = C₂V₂ for any one variable given the other three.
Ideal Gas Law (PV = nRT)
Solve PV = nRT for any of P, V, n, or T.
Buffer (Henderson–Hasselbalch)
pH = pKa + log([A⁻]/[HA]) for buffer solutions.
Normality (N)
Calculate normality = equivalents of solute ÷ liters of solution.
Boyle's Law (P₁V₁ = P₂V₂)
Solve Boyle's law for any of P₁, V₁, P₂, V₂ (constant T).
Osmolarity
Calculate osmolarity = molarity × dissociation factor.
Percent Yield
Calculate percent yield = (actual / theoretical) × 100%.
Atomic Mass Lookup
Look up the atomic mass of any element by symbol (e.g. Fe, Au, U).
Stoichiometry (Moles from Mass)
Calculate moles, atoms, and mass relationships from a chemical formula and mass.
Combined Gas Law
Solve P₁V₁/T₁ = P₂V₂/T₂ for any of P₂, V₂, T₂ (in Kelvin).
Periodic Table (Interactive)
Complete interactive periodic table with all 118 elements. Click any element to see details.