Chemical Name Calculator

Incorrect chemical nomenclature causes misidentification of reagents, failed experiments, and safety hazards. A formula like Fe₂O₃ must resolve to iron(III) oxide, not iron oxide. This tool implements IUPAC 2005 Recommendations for inorganic nomenclature: Stock notation for transition metals, compositional naming with Greek prefixes for covalent compounds, and systematic acid naming. It parses formulas with nested parentheses, assigns oxidation states using electronegativity rules, and computes molar mass from IUPAC 2021 standard atomic weights. Limitation: organic compounds beyond simple functional groups require a full IUPAC organic parser not covered here.

The parser handles formulas like Ca(OH)₂ or K₄[Fe(CN)₆] by tokenizing element symbols, counts, and group delimiters recursively. Molar mass M is computed as M = ∑ n_i ⋅ A_r,i where n_i is the atom count and A_r,i is the standard atomic weight. Pro tip: always verify oxidation states for transition metals. MnO₂ and Mn₂O₇ are very different compounds with very different hazard profiles.

The molar mass of any compound is computed by summing the contribution of each element:

where M = molar mass in g/mol, n_i = number of atoms of element i, A_r,i = standard atomic weight of element i, and k = number of distinct elements.

For ionic compounds with a transition metal, the oxidation state of the metal is determined by balancing total charge to zero. Given a compound M_aX_b where X has known charge q_X:

where q_M = oxidation state of the metal, a = count of metal atoms, b = count of anion groups, q_X = charge of the anion.

Covalent binary compound naming uses Greek prefixes: 1 → mono, 2 → di, 3 → tri, 4 → tetra, and so on. The prefix "mono" is omitted for the first element. Acid naming follows: binary acids use the pattern hydro- + root + -ic acid. Oxyacids with −ate anions become −ic acid; −ite anions become −ous acid.