Chapter 2 Atoms and Elements

2.1 Brownian Motion: Atoms Confirmed

2.2 Early Ideas About the Building Blocks of Matter

2.3 Modern Atomic Theory and the Laws That Led to It

       The Law of Conservation of Mass

       The Law of Definite Proportions

       The Law of Multiple Proportions

       John Dalton and the Atomic Theory

       Chemistry in Your: Day Atoms and Humans

2.4 The Discovery of the Electron

      Cathode Rays

      Millikan's Oil Drop Experiment: The Charge of the Electron

2.5 The Structure of the Atom

2.6 Subatomic Particles: Protons, Neutrons, and Electrons in Atoms

      Elements: Defined by Their Numbers of Protons

      Isotopes: When the Number of Neutrons Varies

      Ions: Losing and Gaining Electrons

     Chemistry in Your Day: Where Did Elements Come From?

 2.7 Finding Patterns: The Periodic Law and the Periodic Table

     Modern Periodic Table Organization

     Ions and the Periodic Table

    Chemistry and Medicine: The Elements of Life

2.8 Atomic Mass: The Average Mass of an Element's Atoms

     Mass Spectrometry: Measuring the Mass of Atoms and Molecules

     Chemistry in Your Day: Evolving Atomic Masses

 2.9 Molar Mass: Counting Atoms by Weighing Them

    The Mole: A Chemist's "Dozen"

    Converting between Number of Moles and Number of Atoms

    Converting between Mass and Amount (Number of Moles)

CHAPTER IN REVIEW: Self-Assessment Quiz

    Key Terms

    Key Concepts

    Key Equations and Relationships

    Key Learning Outcomes

    EXERCISES: Review Questions

    Problems by Topic

    Cumulative Problems

    Challenge Problems

    Conceptual Problems

    Questions for Group Work

    Data Interpretation and Analysis

    Answers to Conceptual Connections