Naming Ionic Compounds Lecture Notes

Introduction

• Focus on naming ionic compounds:
  • Binary ionic compounds
  • Polyatomic ions
  • Transition metals (inclusion of Roman numerals)

Basic Principles

• Ionic Compounds: Composed of a metal and a non-metal.
• Molecular Compounds: Typically consist of two non-metals; naming often includes prefixes (mono-, di-, tri-, tetra-).
• Naming Ionic Compounds: No need for prefixes like in molecular compounds.
  • Name the metal first, followed by the non-metal with the suffix '-ide'.

Examples of Binary Ionic Compounds

1. NaCl: Sodium chloride

   • Na = Sodium
   • Cl = Chloride

2. MgBr₂: Magnesium bromide

   • Mg = Magnesium
   • Br = Bromide

3. AlF₃: Aluminum fluoride

4. CaO: Calcium oxide

5. Sr₃N₂: Strontium nitride

6. BaS: Barium sulfide

Ionic Compounds with Polyatomic Ions

• Polyatomic ions must be memorized or referred to via a sheet.

Examples

1. Li₂SO₄: Lithium sulfate

   • Li = Lithium
   • SO₄ = Sulfate

2. Na₂CO₃: Sodium carbonate

3. Ba(OH)₂: Barium hydroxide

4. KC₂H₃O₂: Potassium acetate

5. Zn(ClO₄)₂: Zinc perchlorate

6. NH₄NO₃: Ammonium nitrate

Transition Metals and Roman Numerals

• Transition metals can have multiple charges; Roman numerals indicate the specific charge in a compound.

Examples

1. FeCl₂ and FeCl₃:

   • FeCl₂ = Iron (II) chloride (Fe²⁺)
   • FeCl₃ = Iron (III) chloride (Fe³⁺)

2. CuBr and CuBr₂:

   • CuBr = Copper (I) bromide (Cu⁺)
   • CuBr₂ = Copper (II) bromide (Cu²⁺)

3. CrS and Cr₂S₃:

   • CrS = Chromium (II) sulfide (Cr²⁺)
   • Cr₂S₃ = Chromium (III) sulfide (Cr³⁺)

4. SnO and SnO₂:

   • SnO = Tin (II) oxide (Sn²⁺)
   • SnO₂ = Tin (IV) oxide (Sn⁴⁺)

Roman Numerals Quick Reference

• I = 1
• II = 2
• III = 3
• IV = 4
• V = 5
• VI = 6
• VII = 7

Complex Compounds

1. PbSO₄: Lead (II) sulfate (Pb²⁺)
2. Pb(CO₃)₂: Lead (IV) carbonate (Pb⁴⁺)

Conclusion

• Understanding the naming conventions and charges is crucial for correctly naming ionic compounds, especially those involving transition metals and polyatomic ions.