Chemical Name Calculator
Determine the name of an ionic compound by selecting the cation and anion, or enter a custom formula. Follows IUPAC nomenclature rules.
Select the positive ion (metal or ammonium)
Select the negative ion (non-metal or polyatomic ion)
Enter a chemical formula directly (optional)
How do you name ionic compounds?
Ionic compounds are named by stating the cation (metal) name first, followed by the anion (non-metal) name with its ending changed to "-ide" (e.g., Chlorine → Chloride). For polyatomic ions, use their specific names (e.g., NO₃⁻ = Nitrate). For transition metals with variable charges, use Roman numerals: Iron(II) chloride = FeCl₂, Iron(III) chloride = FeCl₃.
What are polyatomic ions?
Polyatomic ions are charged groups of atoms that act as a single ion. Common examples: NH₄⁺ (ammonium), OH⁻ (hydroxide), NO₃⁻ (nitrate), SO₄²⁻ (sulfate), CO₃²⁻ (carbonate), PO₄³⁻ (phosphate). They have specific names that must be memorized.
How do you determine the formula from the name?
1) Write the symbols for cation and anion, 2) Note their charges, 3) Cross the charge numbers to get subscripts (Criss-cross method), 4) Simplify to lowest ratio. Example: Aluminum sulfide: Al³⁺ + S²⁻ → Al₂S₃ (cross 3 and 2).
What are the rules for naming hydrates?
Hydrates are ionic compounds with water molecules trapped in their crystal structure. Name the ionic compound first, then add a prefix for the number of water molecules followed by "hydrate": CuSO₄·5H₂O = Copper(II) sulfate pentahydrate. Prefixes: mono- (1), di- (2), tri- (3), tetra- (4), penta- (5), hexa- (6).