Notes: General Chemistry 1A Lecture

Course Overview

• Course Content:

  • Covers first four chapters in Atkins book.
  • Focus on fundamentals reviewed from high school chemistry or Chem 1P.
  • Detailed study of quantum mechanics, molecular structure, and gas properties.
  • Two midterms: first on Chapter 1, second on molecular interaction.

• Homework:

  • Extensive homework set to cover basics.
  • Important sections: A-M in the book (excludes J-K-L).

Significant Figures

• Importance: Essential for precision in calculations.

• Rules:

  • Non-zero numbers are significant.
  • Zeroes between non-zero digits are significant.
  • Leading zeroes are not significant (e.g., 0.00504).
  • Trailing zeros: Significant if there's a decimal (e.g., 2.000).
  • Use scientific notation for clarity in significance.

• Calculations:

  • Addition/Subtraction: Use the lowest number of decimal places.
  • Multiplication/Division: Use the lowest number of significant figures.

Dimensional Analysis

• Purpose: Convert units using conversion factors.
• Method:
  • Write what you have and what you need.
  • Use conversion factors to cancel unwanted units.
  • Keep track of significant figures throughout calculations.

Structure of an Atom

• Basic Model:

  • Nucleus: Protons (positive), Neutrons (neutral).
  • Electrons orbit nucleus (negative).

• Periodic Table:

  • Atomic number = number of protons.
  • Atomic mass = protons + neutrons.

• Isotopes:

  • Atoms with the same number of protons but different neutrons.
  • Periodic table shows weighted average of isotopes.

Periodic Table

• Arrangement: By increasing atomic number in periodic patterns.
• Groups: Elements in the same column have similar properties due to valence electron configuration.

Ionic and Covalent Compounds

• Ionic Bonds:

  • Electrons transferred between atoms.
  • Formation of positive and negative ions.
  • Atoms achieve full octet (8 electrons in outer shell).

• Covalent Bonds:

  • Electrons are shared.
  • Empirical vs. Molecular formula differences.

Naming Compounds

• Types: Ionic, Molecular, Acids, Organic.

• Ionic Naming:

  • Based on charges and crisscross method.
  • Memorize polyatomic ions and specific element charges.

• Naming Rules for Ionic Compounds:

  • Use ion charges to derive formula.
  • Include prefixes/suffixes for multiple oxidation states.

• Polyatomic Ions:

  • Memorize common ions and their charges.
  • Use "-ate" and "-ite" to distinguish oxygen content.

Tips for Study

• Memorization:
  • Important for naming and recognizing compounds.
  • Utilize online study guides and practice resources.
• Utilize Periodic Table:
  • Regularly reference it for valence electrons and ion charges.

Upcoming Topics

• Naming acids and covalent compounds.
• Further exploration of bonding and the periodic table.