1. Introduction to Chemistry
Chapter 1
Introduction to Chemistry

2. What is Chemistry?
Chemistry: the study of matter and the changes that it undergoes
Matter: anything that has mass and takes up space
Mass: a measurement that reflects the amount of matter
Weight: a measurement for the amount of matter and the effect of the Earth’s gravitational pull on that matter
**Because living and nonliving things are made
of matter, chemistry affects all aspects of lift
and most natural events

3. Branches of Chemistry
Organic Chemistry: most carbon containing chemicals
Ex. Pharmaceuticals, plastics
Inorganic Chemistry: in general, matter that doesn’t have carbon
Ex. Minerals, metals & nonmetals, semi-conductors
Physical Chemistry: the behavior and changes of matter and the related energy changes
Ex. Reaction rates, reaction mechanisms
Analytical Chemistry: Components and composition of substances
Ex. Food nutrients, quality control
Biochemistry: Matter and processes of living organisms
Ex. Metabolism, fermentation

4. Technology: the practical use of scientific information
Pure Research: seeks to grain knowledge for the sake of knowledge itself
Applied Research: research undertaken to solve a specific problem or goal
Technology: the practical use of scientific information
Collaboration: a key to being successful in science
When scientists collaborate and communicate, they increase the likelihood of a successful outcome

5. Scientific Method
Scientific Method: a systematic approach used in scientific study
**Question or Problem
Observation: existing knowledge
Qualitative Data: information that describes color, odor, shape, and other physical characteristics
Quantitative Data: numerical information
Hypothesis: a tentative explanation for what has been observed, and that can be tested
Experiment: a set of controlled observation that test the hypothesis
Independent Variable: in an experiment, that variable the experimenter plans to change
Dependent Variable: in an experiment, the variable whose value depends on the independent variable
Control: in an experiment, the standard that is used for comparison
Conclusion: a judgement based on the information obtained
Theory: is an explanation that has been supported by many, many experiments
Scientific Law: describes a relationship in nature that is supported by many experiments (doesn’t try to explain)

6. Scientific Theory vs. Law
Scientific Theory: explains a large number of facts and hypothesis
Has withstood much testing
Is synonymous to fact
Plate tectonics is a theory built of many hypotheses of plate motion
Scientific Law: describes a relationship in nature that is supported by many experiments
Law of Gravity
Newton’s Laws of Motion

8. A scientific inquiry Step One: Collection or Observations
Dinosaurs ~65 Ma
Many other organisms ~65 Ma
Iridium (Ir) present at extinction
Iridium (a metal) is found in meteorites, comets, certain lavas, and cosmic dust. Not normally found in high concentration at Earth’s surface

9. A Scientific Inquiry Step Two: Hypothesis development Testable?
Comet or asteroid impact created the iridium anomaly
Testable?
Side effects?
Dust cloud
Fireball
“Nuclear” winter
Instant death

10. A Scientific Inquiry Step Three: Observations and Experiments
Test for iridium world-wide
Test for abrupt end to dinosaurs and plankton
Crater?

11. A Scientific Inquiry Steps Four & Five: Accept, modify, reject?
Iridium is world-wide
Almost abrupt end to dinosaurs and plankton
Later crater & soot found (Mexico's Yucatan Peninsula)