Introduction to Geochemistry

This is a working draft of An Introduction to Geochemistry textbook to be used by Geology and Environmental Geosciences majors for GEOL 250: Introduction to Geochemistry class at the College of Charleston. One semester of chemistry (CHEM 111 or equivalent) is a prerequisite for this course.

The first chapter summarizes atomic principles, including the periodic table and chemical reactions. The subsequent two chapters focus on thermodynamics and chemical equilibrium principles foundational to environmental geosciences. These fundamental geochemical concepts are applied to our understanding of geological and environmental processes. The rest of the textbook introduces topics such as acids and bases, redox processes, chemical kinetics, environmental isotopes, and environmental organic chemistry. Students are strongly advised to use this textbook, provided class notes, and all suggested readings for more in-depth understanding.

I incorporated several examples and practice exercises throughout the textbook. I have also incorporated short case studies and links to topic-related videos created by many content creators. I will continue to add and improve these exercises to help you understand and apply the concepts better.

Atoms First

• 1 Atoms First
• 1.1 Atoms and Subatomic Particles
• 1.2 The Periodic Table
• 1.3 Chemical Bonding
• 1.4 Chemical Reactions
• 1.5 Practice Problems

Thermodynamics

• 2 Thermodynamics
• 2.1 Energy and Thermochemistry
• 2.2 The Zeroth Law
• 2.3 The First Law
• 2.4 The Second Law
• 2.5 The Third Law
• 2.6 Gibbs Free Energy
• 2.7 Practice Problems

Chemical Equilibrium

• 3 Chemical Equilibrium
• 3.1 What is Equilibrium?
• 3.2 Law of Mass Action
• 3.3 Application of \(K\)
• 3.4 Practice Problems

Acids and Bases

• 4 Acids and Bases
• 4.1 What are Acids and Bases?
• 4.2 Strength of Acids and Bases
• 4.3 Salts of Acids and Bases
• 4.4 Practice Problems

Reduction and Oxidation Processes

• 5 Redox Chemistry
• 5.1 What is Oxidation and Reduction?
• 5.2 Balancing Redox Reactions
• 5.3 Electron Activity, \(pe\)
• 5.4 Practice Problems

Kinetics of Reactions

• 6 Chemical Kinetics
• 6.1 Chemical Kinetics
• 6.2 Common Rate Expressions
• 6.3 Practice Problems

Environmental Isotopes

• 7 Environmental Isotopes
• 7.1 Radioisotopes
• 7.2 Stable Isotopes
• 7.3 Practice Problems

Environmental Organic Chemistry

• 8 Environmental Organic Chemistry
• 8.1 What are organic chemicals?
• 8.2 Organic Chemicals in the Environment
• 8.3 Practice Problems

Appendices

• Review of Basic Mathematics