Lecture Notes: Naming Ionic and Molecular Compounds

Introduction

• Presenter: Melissa Maribel
• Focus: Understanding how to name ionic and covalent (molecular) compounds.
• Importance: Essential skill throughout chemistry, needed for future courses.

Strategy for Naming Compounds

• Identify the Compound Type
  • Ionic Compounds: One metal and one nonmetal.
  • Covalent Compounds: Two nonmetals.

Ionic Compounds

1. Ionic Compounds without Transition Metal

• Naming: Metal + Nonmetal ending in "-ide"
• Example: Aluminum Oxide
  • Aluminum (metal) and oxygen (nonmetal) balanced by charges.
  • Aluminum Charge: 3+
  • Oxygen Charge: 2-
  • Balanced Compound: Subscripts 2 for Aluminum and 3 for Oxygen.
• "Lasso" Method: Assign opposite charges to balance and cancel each other.

2. Ionic Compounds with Transition Metal

• Naming: Transition Metal + Roman Numeral + Nonmetal ending in "-ide"
• Example: Iron (III) Oxide
  • Iron charge indicated by Roman numeral (III = 3+).
  • Balanced with Oxygen (2- charge) by subscripts 2 for Iron and 3 for Oxygen.
  • Resulting Compound: Fe2O3

3. Ionic Compounds with Polyatomic Atoms

• Polyatomic Atoms: Composed of two or more elements, often ending in "-ate" or "-ite."
• Example: Calcium Phosphate
  • Calcium (2+ charge) and Phosphate (3- charge).
  • Use parentheses for polyatomic groups.
  • Resulting Compound: Calcium subscript 3 with Phosphate subscript 2.

4. Transition Metals with Polyatomic Atoms

• Naming: Transition Metal + Roman Numeral + Polyatomic Atom
• Example: Copper (II) Nitrate
  • Copper charge (II = 2+) balanced with Nitrate (NO3 with -1 charge).
  • Use parentheses for nitrate when adding subscript.

Covalent (Molecular) Compounds

Key Points

• Consist of two nonmetals.
• Use prefixes to define quantity (1-10).
• No need to balance charges.

Naming Method

• Prefix + Nonmetal + Prefix + Nonmetal ending in "-ide"
• Example: Diphosphorus Pentoxide
  • "Di" = 2, "Pent" = 5

Example: N3O6

• Naming: Trinitrogen Hexaoxide
  • "Tri" = 3 for Nitrogen, "Hexa" = 6 for Oxygen.

Final Thoughts

• Practice is crucial for mastering compound naming.
• Encouragement to pursue ambitious career goals with confidence.
• Online tutoring available for additional help.

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Note: Use a periodic table and flashcards to memorize charges and polyatomic atoms for effective learning.