chapter 1 Chemistry is a science (to student).pdfVIP

Chemistry 1010 Instructor: Bingwu Wang Email: wxjsbuct2001@163.com Introduction Chapter 1 Chemistry is a science 1.1 Chemistry is a central science useful to our lives ? Would you prefer to live without medicines, or anything made of plastic or metal? ? Chemistry is the study of matter and the transformations it can undergo. ? Chemistry is often described as a central science because it touches all the other sciences. ? biology ? geology ? space science ? basic research ? applied research Concept check ? Chemists have learned how to produce aspirin by chemical reactions. Is this an example of basic or applied research? 1.2 Science is a way of understanding the universe ? Science is an organized body of knowledge about nature, a way of exploring nature, a tool for solving problems. scientific method Why? predictions and tests ? the experimental test and its control test ? The two tests differ by only one variable. ? Reproducibility and an correct attitude are essential components of science. ? The results of a scientific experiment are considered valid only if they can be reproduced by other scientists. ? The attitude is one of inquiry, experimentation honesty and a faith that all natural phenomena can be explained. ? scientific hypothesis: a testable assumption, or guess, often used to explain an observed phenomenon. ? theory: a wide range of observations can be explained by a single comprehensive idea that has stood up to repeated scrutiny. ? the theory of natural selection ? Science has limitations. ? Science deals only with hypotheses that are testable, its domain is the natural world. ? Science is unable to answer such philosophical questions as “what is the purpose of life?” 1.3 Scientists Measure Physical Quantities ? physical quantity ? length ? time ? mass ? weight ? volume ? temperature ? the U. S. Customary System (USCS) or the British System of Units ? the International System of Units (SI) or the metric system decimal system of SI