Overview
This lecture covered the naming and formulas of common binary ionic compounds, focusing on metals with nonmetals, anion suffixes, and key examples for chemistry students.
Naming Binary Ionic Compounds
- Binary ionic compounds are made of a metal (cation) and a nonmetal (anion).
- The cation is named first, followed by the anion.
- The anion name typically ends with "-ide" (e.g., chloride, oxide, sulfide).
- Examples: sodium chloride (NaCl), magnesium oxide (MgO), calcium bromide (CaBr₂).
Common Cations (Metals)
- Sodium (Na⁺), potassium (K⁺), calcium (Ca²⁺), aluminum (Al³⁺), magnesium (Mg²⁺), lithium (Li⁺), zinc (Zn²⁺), barium (Ba²⁺).
- The metal’s name stays the same in the compound.
Common Anions (Nonmetals)
- Chloride (Cl⁻), bromide (Br⁻), iodide (I⁻), oxide (O²⁻), sulfide (S²⁻), nitride (N³⁻), hydride (H⁻), fluoride (F⁻), phosphide (P³⁻).
- The nonmetal’s root name is used with "-ide" appended.
Examples of Compound Names and Formulas
- Sodium chloride: NaCl
- Potassium bromide: KBr
- Magnesium oxide: MgO
- Calcium sulfide: CaS
- Aluminium chloride: AlCl₃
- Lithium fluoride: LiF
- Barium hydride: BaH₂
- Calcium hydride: CaH₂
- Aluminium tribromide: AlBr₃
- Magnesium nitride: Mg₃N₂
- Sodium sulfide: Na₂S
Notes on Polyatomic Ions and Variants
- Some suffixes like "-ite" or "-ate" (e.g., sulfite, nitrite) refer to polyatomic ions, but main focus here is on "-ide" for binary compounds.
- Prefixes (tri-, di-) indicate multiple atoms (e.g., aluminium tribromide: AlBr₃).
Key Terms & Definitions
- Cation — Positively charged ion, typically a metal in ionic compounds.
- Anion — Negatively charged ion, typically a nonmetal in ionic compounds.
- Binary Ionic Compound — Compound containing only two elements: one metal and one nonmetal.
- Suffix "-ide" — Indicates a simple anion formed from a nonmetal.
Action Items / Next Steps
- Practice writing names and formulas for given binary ionic compounds.
- Review polyatomic ions and their naming conventions.
- Complete assigned homework on compound naming.