Ch. 1: The Chemical WorldCh. 1: The Chemical World

Dr. Namphol Sinkaset

Chem 152: Introduction to General Chemistry

I. Chapter OutlineI. Chapter Outline

I. IntroductionII. Atoms and MoleculesIII. The Scientific MethodIV. Succeeding in Chemistry

I. Layman’s View of I. Layman’s View of ChemicalsChemicals

I. Educated View of ChemicalsI. Educated View of Chemicals

I. The Nature of ChemistryI. The Nature of Chemistry

• Revolves around the question “Why?”

• Make connections between macroscopic and microscopic behavior.

II. Atoms and Molecules II. Atoms and Molecules

• Microscopic view refers to atoms.• Atoms can bind together to form

molecules.• chemistry: the science that seeks to

understand what matter does by studying what atoms/molecules do

II. Carbon Dioxide and WaterII. Carbon Dioxide and Water

III. The Scientific MethodIII. The Scientific Method

• A way of learning that emphasizes observation and experimentation.

III. It Begins w/ ObservationsIII. It Begins w/ Observations

• Scientists begin their study by making an observation or measurement.

• Observation can be simple description or complex measurement.

• e.g. Fleming noticed bacteria-free rings around a certain mold.

• e.g. Lavoisier measured masses before and after combustion reactions.

III. A Hypothesis is Formed III. A Hypothesis is Formed and Testedand Tested

• Observations lead to preliminary interpretation or explanation.

• The hypothesis should be falsifiable.• Hypotheses are tested via experiments.• experiment: highly controlled observations

designed to validate/invalidate a hypothesis.

• Results may lead to revision of hypothesis.

III. Scientific LawsIII. Scientific Laws

• Many similar observations may be developed into a scientific law.

• scientific law: statement that synthesizes past observations and predicts future ones

• Laws can be tested with experiments as well.

III. TheoriesIII. Theories

• One or more well-established hypotheses can be formulated into a theory.

• theory: models of nature that provide a broader and deeper explanation of observations and laws

• A lot of work goes into formulating a theory; they are the height of scientific understanding…not “just a theory.”

IV. Keys to SuccessIV. Keys to Success

• Curiosity – you need to be interested in finding out the “why” of things.

• Math – you need to have the math skills to deal with and calculate quantities in chemistry.

• Hard work – you need to be able to commit the time and effort to be successful.