1.2 –Chemistry and Matter Objectives: Describe chemistry Understand why you’re here Describe a few careers in chemistry

1.2 – Chemistry & Matter Chemistry: the study of matter and its changes Chemistry considers: The properties of the starting and ending substances, The reasons they change, The energy involved as they change, The time it takes for them to change, and most importantly, How to measure all these things.

1.2 – Chemistry & Matter A Brief History of Chemistry Early practical chemistry: household goods weapons soap wine basic medicine As early as 400 BCE the Greeks had developed the idea of ‘atomism’ – the idea that everything is composed entirely of various imperishable, indivisible elements called atoms. (Atomism may even go back to 1200-1300 BCE.)

1.2 – Chemistry & Matter A Brief History of Chemistry Alchemy was the quest for: the Philosopher’s Stone - a substance that could turn metals into gold, and the elixir of life that would make the drinker immortal. Alchemy was practiced throughout the ancient world including China, the Middle East and ultimately Europe. Nicolas Flamel actually was an alchemist, as was Isaac Newton. Lead Mercury Gold Antimony Bismuth Arsenic Copper Iron Magnesium

1.2 – Chemistry & Matter A Brief History of Chemistry Alchemy’s contributions to chemistry experimental techniques new glassware information about elements developed several alloys Modern chemistry started in the 18th century Antoine Lavoisier the father of modern chemistry Benjamin Franklin the nature of electrical charges John Dalton the atomic theory

1.2 – Chemistry & Matter Fields of Chemistry Inorganic chemistry – matter not containing carbon Organic chemistry – matter containing carbon Physical chemistry – matter & energy Analytical chemistry – testing matter for its make up Biochemistry – matter interactions in living organisms Theoretical chemistry – subatomic interactions

1.2 – Chemistry & Matter What can Chemistry offer me? A basic understanding of : how stuff is put together why certain things happen in our environment scientific processes How to think about cause and effect Problem solving skills including study skills Communication skills A taste of physical science to see how you like it. What Chemistry isn’t Blowing stuff up Optional, if you plan on going to a 4 year college Easy A class to mess around in

1.2 – Chemistry & Matter CHEMISTRY Chemistry’s universality Engineer Pharmacist Biologist HVAC Technician Geologist Manicurist CHEMISTRY The Central Science Doctor Physicist Chef Makeup Artist Chemist Musician?

1.3 –Scientific Methods Objectives: Describe the steps of the scientific method Describe why the scientific method is needed Differentiate between qualitative & quantitative observations Differentiate between independent & dependent variables Evaluate an experiment for validity Evaluate data for reliability Describe the value of scientific models Describe how experimentation leads to scientific theories and natural laws

1.3 – Scientific Methods  What is the Scientific Method? An organized set of steps to communicate to others how a question has arisen, been considered, and answered Directly related to observational skills A problem solving procedure that you use daily A learning cycle What is the point of the Scientific Method? To gain enough information to be able to make predictions about cause and effect, or at least correlation To explain the world around us 

1.3 – Scientific Methods Steps of the Scientific Method Observation Research Hypothesis Experiment Analyze Results Conclusions Observation Question Hypothesis Experiment Conclusions The process is a cycle that keeps going until science has reached enough understanding to develop a theory.

1.3 – Scientific Methods Steps of the Scientific Method 1. Observation Something has to happen to inspire our curiosity. Qualitative observations – based on physical characteristics (color, odor, shape, etc. – typically subjective descriptions based on the five senses) Quantitative observations – based on numerical data or measurements (length, temperature, etc. – objective, based on standards and universally accepted) Inference–the act or process of deriving logical conclusions from premises known or assumed to be true. Inference does not make for good science.

1.3 – Scientific Methods Steps of the Scientific Method 2. Research How or why does something occur? Gain background knowledge 3. Hypothesis After considerable research, a proposed answer to the question is presented for testing. A good hypothesis must be testable and falsifiable. Usually an “If, then” statement. Scientists seek to disprove their hypothesis, not to prove it. This is what Einstein meant when he said, "No amount of experimentation can ever prove me right; a single experiment can prove me wrong."

1.3 – Scientific Methods Steps of the Scientific Method 4. Experiment Designed to allow for a controlled set of observations to occur. Assigning variables Independent variable – that aspect of the experiment that is deliberately varied from trial to trial (what you change) Dependent variable – the value the scientist measures which changes as a result of manipulating the independent variable. (what you measure)

1.3 – Scientific Methods Steps of the Scientific Method 4. Experiment Experimental Control A control group is used as a comparison. The control group is designed to behave in a predictable way. Each experimental group will vary from the control group in only 1 way. The experimental and control groups will otherwise be identical.

1.3 – Scientific Methods Steps of the Scientific Method 4. Experiment Validity & Reliability Validity is a characteristic of an experiment that indicates if the experiment is truly measuring or testing the thing it intends to. Reliability is a characteristic of an experiment that indicates if the results will be reproducible.

1.3 – Scientific Methods Steps of the Scientific Method 5. Conclusions Based on analysis of data, a proposed answer to why or how this event occurs is advanced. Experiments are done repeatedly in an attempt to disprove the hypothesis. The more failed attempts to disprove the hypothesis, the greater the likelihood that the hypothesis is true. Valid & reliable conclusions lead to models which may be used to make predictions which can then be tested. may advance to the status of natural laws or theories.

1.3 – Scientific Methods Steps of the Scientific Method 5. Conclusions Theory – Describes how and why an event occurs. Theories cannot be proven 100% true, but they are as close as scientists can get. They are essentially ‘facts’, however, they do occasionally change as new evidence becomes available. Scientific (Natural) Law – Describes how an event will always occur, but not why. Are easier to derive than theories.

1.4 – Scientific Research Objectives: Describe the difference between pure and applied research Relate chemistry to technology

1.4 – Scientific Research Scientific Research Pure Research to explain natural phenomena motivated by curiosity Applied Research to solve specific identified problems motivated by need Chance Discoveries sometimes you get lucky, but you have to be able to see it nylon, radiation, penicillin, silly putty Benefits of Chemistry Technology – the practical use of scientific knowledge to improve the quality of life.