So today several people stayed late after class worried about the test next week. I'm happy to see that you care about the class so much! This is an encouraging sign to me that you are serious about your work and that you will succeed in this class!
However, the question is always more geared towards this: "How can I possibly get an A in this class? I've studied really hard and I'm still getting 6/10 on my quizzes and I don't understand the labs...."
To you who feel this way I sympathize. It was not long ago I felt very similarly. The encouraging part of this is that it will get better. Continue to review lecture notes, try to form study groups with each other and work as many practice problems as you can from the book. Eventually the vocabular will begin to sink in and you will see the many patterns and all of the repetition that exists in the material. It is there. You just may not be able to see it yet.
So- I am leaving for a family reunion and want to give my last review for our test on Thurs on ch 1-3. I figured this would be a great blog post not to mention a great way to recruit more traffic on my site. Not only do you get 1-2 points of extra credit for a pithy comment but you get extra exam review also! What a deal.
So the crux of chapters 1-3 goes like this: (Credit to the Introductory Chemistry text by Bauer here)
Chapter 1 is focused primarily on the definition of science, explanation of chemistry and the breakdown of matter. What is chemistry and how does it differ from other forms of academic thought? The biggest difference between science/chemistry and other forms of nonscientific thought is that science uses experimentation to test out ideas. The philosophers during the middle ages were excellent at reasoning: Plato and Socrates formulated ideas from which an entire family tree of philosophers descended, however, they never tested out any of their ideas experimentally. So- while many disciplines use logic, science is special in its use of experimentation.
The definition and classification of matter is something you should review. What is the difference between matter and energy? Can you name examples of each?
Matter is subdivided into subcategories of substance vs mixture. Substances are pure in that they always have uniform composition with the same chemical and physical properties throughout. Only elements and compounds quality as pure substances. Mixtures are more tricky. A mixture is, by definition, something that contains multiple pure substances fixed in variable proportions. So, a mixture may or may not have the same composition throughout. For this reason, a subcategory has been established that differentiates between homogeneous and heterogeneous mixtures. Homogeneous mixtures (like solutions) are the same throughout while heterogeneous mixtures have a variable composition throughout. A mixture can always be separated into its different chemical components by some type of physical separation. (Filtration, evaporation, decantation, distillation, extraction, etc.)
This brings us to the discussion of states of matter. Matter can change forms without changing chemical composition. The different physical forms of matter form different states: solid, liquid and gas. These each have specific definitions and descriptions.
Energy is the ability to do work. There are all types of energies out there but the two main kinds are kinetic and potential. Within these two subdivisions are different subtypes like chemical energy, electric energy, heat energy, thermal energy, elastic energy, and many others. It is a good exercise to imagine a moving object and label the type of energy it has in various stages of movement.
Chapter 1 also covers the scientific method. The scientific method is a way of asking questions about the physical world and implementing a system of inquiry to answer those questions. Whether you hypothesize about a potential outcome or actually formulate scientific laws and theories on well-documented data, you employ the process. Review the different terms of the scientific method and familiarize yourself with them.
Chapter 1 introduces the periodic table and the classification of metals, nonmetals and metalloids. Each category embodies some similar properties of its element type. What are these properties and which elements fit into each? How would you determine this just by looking at the periodic table?
And finally conversions, significant digits, rounding, scientific notation and the entire math toolbox in chapter 1 will be critical to your success throughout this class and in the next class, Chemistry 1A. I recommend you master the entire toolbox for maximum learning.
Chapter 2 is my personal favorite out of ch 1,2 and 3 because it delves into the history of science. I personally believe our nation would be much more scientifically savvy if our education system required everybody to study the history of science in chronology with the actual content of science classes. I actually ran into someone today who knew of a program at Harvey Mudd that tried to implement such a system. Apparently it is too time consuming for students' schedules to make it work effectively. Interesting idea, however.
Chapter 2 follows the initial idea about atoms from Democritus (Greek philosopher) in 450 BC. From here, atoms were born. Dalton formulated his atomic theory based on the ideas of Proust (law of definite proportions), Lavoisier (conservation of matter) and other information to form the four tenants of atomic theory. Note that this theory is our first exposure to a scientific theory in the chemistry text. Why is it a theory? Because it provides a broad definition of nature that incorporates scientific laws (Proust's and Lavoisier's) but it goes further to suggest something that is true of all of nature. And, like any theory it can be modified and changed as further evidence becomes available.
I will post more as another entry.
