6.3 Chemical Formula and Name of Binary Ionic Compounds
Binary Ionic Compounds:
Composed of mono-atomic metal cations and mono-atomic non-metal anions.
Naming convention: Cation name first, followed by anion name.
Cation name: Same as the metal name.
Anion name: Root name of the element + suffix 'ide'.
Examples: Sodium chloride, magnesium oxide, aluminium nitride.
Steps to Write Chemical Formula of Binary Ionic Compounds:
- Write symbols for cation first, then anion, including their charges.
- Balance charges using smallest coefficients (compound must be neutral).
- Write coefficients as subscripts for each ion.
- Omit charge subscripts of 1 in the final formula.
Examples:
- Sodium chloride: Na⁺ Cl⁻ → NaCl
- Aluminium oxide: Al³⁺ O²⁻ → Al₂O₃
Common Cations and Anions:
Cations:
- Lithium
- Sodium
- Potassium
- Magnesium
- Calcium
- Copper
Anions:
- Fluoride
- Chloride
- Bromide
- Nitrite
- Nitrate
- Sulfate
Note: This section covers the basics of naming and writing formulas for binary ionic compounds. It emphasizes the importance of charge balancing and provides a list of common cations and anions for reference.