chem 120Midterm Study Guide

Science is an accumulation of knowledge about nature and our physical world and of theories that we use to explain that knowledge.  The experimental roots of chemistry are in alchemy, a mixture of chemistry and mag ...

Science is an accumulation of knowledge about nature and our physical world and of theories that we use to explain that knowledge.  The experimental roots of chemistry are in alchemy, a mixture of chemistry and magic  How to design and document an experiment o Ask a question  Do background research  Construct a hypothesis  test your hypothesis by doing an experiment  analyze your data and draw a conclusion  report your results (was your hypothesis correct?) o Five steps in the scientific method  Describe and formulate a question to answer  formulate a hypothesis: A statement that predicts what you think will happen  Develop an experiment  Observe and analyze the results  state your conclusion. Did you accept or reject the hypothesis? What have you learned based on the information collected?  Characteristics or components of science o Reproducibility, Testability, Tentativeness, Predictability, Explanatory  A variable is something that can change over the course of an experiment. o Disagreement often results from the inability to control variables  Concepts of scientific law and theory o Large amounts of scientific data can sometimes be summarized in brief statements called scientific laws. Many scientific laws can be stated mathematically and are universal. Under the specified conditions, they hold everywhere in the observable universe. o Scientists organize the knowledge they accumulate on a framework of detailed explanations called theories. A theory represents the best current explanation for a phenomenon, but it is always tentative. Theories that make successful predictions are usuall