Overview
This set reviews key ions and their patterns to help students memorize common cations, anions, and polyatomic ions needed in chemistry courses.
Common Monatomic Ions
- Group 1 elements form 1+ ions (e.g., Na⁺, K⁺).
- Group 2 elements form 2+ ions (e.g., Ca²⁺, Mg²⁺).
- Group 13 elements form 3+ ions (e.g., Al³⁺).
- Group 14 elements can form 4+ or 4− ions.
- Group 15 elements form 3− ions (name: root+ide, e.g., nitride).
- Group 16 elements form 2− ions (name: root+ide, e.g., oxide).
- Group 17 elements form 1− ions (name: root+ide, e.g., chloride).
Transition Metal Ions with Roman Numerals
- Copper: Cu⁺ (I), Cu²⁺ (II).
- Chromium: Cr³⁺ (III), Cr⁶⁺ (VI).
- Iron: Fe²⁺ (II), Fe³⁺ (III).
- Lead: Pb²⁺ (II), Pb⁴⁺ (IV).
- Manganese: Mn²⁺ (II), Mn⁴⁺ (IV), Mn⁷⁺ (VII).
- Mercury: Hg₂²⁺ (I), Hg²⁺ (II).
- Tin: Sn²⁺ (II), Sn⁴⁺ (IV).
- Silver: Ag⁺.
- Zinc: Zn²⁺.
Common Polyatomic Ions
- Ammonium: NH₄⁺.
- Acetate: CH₃COO⁻ or C₂H₃O₂⁻.
- Carbonate: CO₃²⁻.
- Hydrogen Carbonate (bicarbonate): HCO₃⁻.
- Perchlorate: ClO₄⁻.
- Chlorate: ClO₃⁻.
- Chlorite: ClO₂⁻.
- Hypochlorite: ClO⁻.
- Chromate: CrO₄²⁻.
- Dichromate: Cr₂O₇²⁻.
- Cyanide: CN⁻.
- Thiocyanate: SCN⁻.
- Hydride: H⁻.
- Hydroxide: OH⁻.
- Nitrate: NO₃⁻.
- Nitrite: NO₂⁻.
- Permanganate: MnO₄⁻.
- Manganate: MnO₄²⁻.
- Peroxide: O₂²⁻.
- Phosphate: PO₄³⁻.
- Hydrogen Phosphate: HPO₄²⁻.
- Dihydrogen Phosphate: H₂PO₄⁻.
- Sulfate: SO₄²⁻.
- Hydrogen Sulfate (Bisulfate): HSO₄⁻.
- Sulfite: SO₃²⁻.
- Hydrogen Sulfite (Bisulfite): HSO₃⁻.
- Oxalate: C₂O₄²⁻.
- Thiosulfate: S₂O₃²⁻.
- Iodate: IO₃⁻.
- Bromate: BrO₃⁻.
Patterns and Nomenclature
- Ions ending in '-ate' correspond to "(root)ic" acids.
- Ions ending in '-ite' correspond to "(root)ous" acids.
- Ions ending in '-ide' correspond to "hydro(root)ic" acids.
- Roman numerals indicate the charge on the ion.
Key Terms & Definitions
- Monatomic Ion — ion consisting of a single atom.
- Polyatomic Ion — ion consisting of multiple atoms bonded together.
- Roman Numeral — indicates the charge of a transition metal ion.
Action Items / Next Steps
- Memorize the listed ions and their charges.
- Practice writing formulas from ion names and charges.
- Review acid naming conventions associated with each ion.