Chapter 1

1. Chapter 1 Introduction to Chemistry by Christopher Hamaker Chapter 1

2. Evolution of Chemistry • The Greeks believed in four basic elements: 1. Earth • Air • Fire • Water • All substances were combinations of these four basic elements. Chapter 1

3. Scientific Investigations • Science is the methodical exploration of nature followed by a logical explanation of the observations. • Scientific investigation entails the following activities: • Planning an investigation • Carefully recording observations • Gathering data • Analyzing the results Chapter 1

4. The Scientific Method • The scientific methodis a systematic investigation of nature and requires proposing an explanation for the results of an experiment in the form of a general principle. • The initial, tentative proposal of a scientific principle is called a hypothesis. • After further investigation, the original hypothesis may be rejected, revised, or elevated to the status of a scientific principle. Chapter 1

5. Applying the Scientific Method Step 1: Perform a planned experiment, make observations, and record data. Step 2: Analyze the data and propose a tentative hypothesis to explain the experimental observations. Step 3: Conduct additional experiments to test the hypothesis. If the evidence supports the initial proposal, the hypothesis may become a theory. Chapter 1

6. Applying the Scientific Method, Continued • After sufficient evidence, a hypothesis becomes a scientific theory. • A natural law is a measurable relationship. Chapter 1

7. Critical Thinking: Reactions with Oxygen What do burning wood, rusting iron, and exploding gasoline have in common? • All three are examples of combustion. • Combustion is a chemical reaction of a substance with oxygen. • Rusting is a slow reaction, burning is a rapid reaction, and an explosion is an instantaneous reaction. Chapter 1

8. Modern Chemistry • Chemistry is a science that studies the composition of matter and its properties. • Chemistry is divided into several branches: • Organic chemistry is the study of substances containing carbon. • Inorganic chemistry is the study of all other substances that don’t contain carbon. • Biochemistry is the study of substances derived from plants and animals. Chapter 1

9. Learning Chemistry • Different people learn chemistry differently. • What do you see in the picture? • Some people see a vase on a dark background; some people see two faces. Chapter 1

10. Problem Solving • Connect the dots using only four straight lines. • Experiment until you find a solution. • Did you have to use five straight lines? • No matter which dot we start with, we still need five lines. Chapter 1

11. Problem Solving, Continued • Are we confining the problem? • We need to go beyond the nine dots to answer the problem. Chapter 1

12. Chemistry: The Central Science • Knowledge of chemistry is important to understanding the world around us. Chapter 1

13. Chapter Summary • Scientists use the scientific method to investigate the world around them. • Experiments lead to a hypothesis, which may lead to a scientific theory or a natural law. • Chemistry is a central science with many branches. • The impact of chemistry is felt in many aspects of our daily lives. Chapter 1