What is chemistry?

1. What is chemistry? Chapter 1

2. What is chemistry? • Matter is anything that has mass and occupies space • Do you have to see something for it to qualify as matter? Why or why not? • Chemistry: study of the composition of matter and the changes that matter undergoes • Because living and nonliving things are made of matter, chemistry affects all aspects of life and most natural events • Therefore chemistry=life!

3. Areas of study • The scope of chemistry is vast, 5 areas to focus on: • Organic chemistry: study of chemicals containing carbon • Inorganic chemistry: study of chemicals that generally do not contain carbon • Biochemistry: study of processes that take place in an organism • Analytical chemistry: study that focuses on the composition of matter • Physical chemistry: deals with mechanisms, rates, and energy transfer that occurs when matter undergoes a change • Pg 8 lists examples of each branch. List these examples in your notes • Answer the “Inferring” question in the caption of Fig 1.2

4. Pure and applied chem • Pure chemistry: pursuit of knowledge for its own sake (no practical use to knowledge gained) • Applied chemistry: research that is directed towards a practical goal • Pure research can lead directly to an application, but an application can exist before research is done to explain how it works

5. Aspirin “fun” Fact • In the late 1840’s, Dr. Lawrence Craven observed that gum containing aspirin, which was used to relieve pain after the removal of tonsils, caused excessive bleeding in children. He hypothesized that aspirin prevented the blood from clotting, and began prescribing it to prevent heart attacks. • In 1985, the FDA approved aspirin for patients who had suffered a heart attack. • In 1996, the FDA proposed using aspirin during a suspected attack. • In 1997, an advisory committee recommended daily low doses for people at high risk of heart attack

6. Why study chemistry? • Chemistry can be useful in explaining the natural world, preparing people for career opportunities, and producing informed citizens. • Look on pg 10-11 for reasons why

7. Define: • Macroscopic: • Microscopic: • Biotechnology: • Pollutant: • What impact do chemists have on materials, energy, medicine, agriculture, the environment, and the study of the universe?

8. Think like a scientist • 1928 Alexander Fleming noticed a bacteria did not grow around a yellow green mold. He assumed that the mold produced a chemical that killed the bacteria. This mold was penicillin • “Chemistry” comes from “alchemy.” Long before chemists, there were alchemists that studied matter, and developed techniques for working with chemicals.

9. The scientific Method • A logical, systematic approach for the solution to a problem • Condensed approach to the scientific method include making observations, testing hypotheses, and developing theories.

10. Making observations • Use your 5 senses to obtain information • An observation leads to a question. • What are some observations you can make about this classroom?

11. Inference • From the observations, we can make inferences • These answer questions based on the observations. • Example: • Observation: The dog is barking • Inference: There is an intruder • What are other possible inferences for this observation

12. Testing hypotheses • A hypothesis is a proposed explanation for an observation • An experiment is done to test the hypothesis. • When you design experiments, you deal with variables, or factors that change • Variables that change during an experiment is the manipulated variable, or independent variable • The variable that is observed during an experiment is the responding variable, or dependent variable • Control group: group with a placebo

13. Developing theories • A theory is a well tested explanation for a broad set of observations. • Theories may not be able to be proven, but that does not make them unreliable. • What are some examples of theories you can think of?

14. Scientific laws • A scientific law is a concise statement that summarizes the results of many observations and experiments. • What are some laws you can think of?

15. Communication and collaboration • When scientists collaborate and communicate effectively, they increase the likelihood of successful outcomes. • Discussion • What are some times that communication between scientists is useful? • How do you think scientific journals are useful for this?