The Scientific Method
What is chemistry? The study of matter, its structure, properties, and composition, and the changes it undergoes.
How do scientists approach problems? Pure science: science that seeks to gain knowledge Applied science: science that seeks to solve a problem Also known as technology
What is scientific knowledge based upon? Scientific knowledge is based on observations These observations lead to asking questions Problems are solved using the scientific method
What is the scientific method? A logical approach to the solution of a problem or question that has been raised through observation
What are the steps in the scientific method? Make observations about a phenomenon State a problem based on observations made (usually in the form of a question) Research Form a hypothesis Test the hypothesis using an experiment Collect data Repeat experiment Analyze and interpret the data State conclusions
What is a hypothesis? A reasonable explanation for an observed phenomenon
What is an experiment? A process carried out under controlled conditions to test the validity of a hypothesis
What are the parts of an experiment? Constant: factors that remain the same during the experiment Control: responds in a predictable way to the experiment Variables: factors that change during the experiment
What are the two types of variables? Independent: factors the experimenter has control over (manipulated factors) Dependent: factors that change as a result of a change in the independent variable (responsive factors)
What is a theory? An explanation of observations that are based on experimentation and reasoning Examples of theories include cellular theory, atomic theory, molecular theory, evolutionary theory, the theory of plate tectonics, the theory of relativity, gravitational theory
When does a hypothesis become a theory? A theory is developed from a hypothesis that has withstood years of experimentation
What is a scientific law? An explanation of the natural world Laws are usually a statement of a single observable phenomenon, such as Newton’s Laws of Motion
How does a theory become a law? Theories that withstand experimentation become scientific law Both scientific theories and laws can be proved incorrect