Chapter 2: Measurements and Calculations Section 1: Scientific method

Section 1: scientific method Objectives Describe the purpose of the scientific method. Distinguish between qualitative and quantitative observations. Describe the differences between hypotheses, theories, and models.

Scientific method The scientific method is a logical approach to solving problems by OBSERVING and COLLECTING DATA, FORMULATING HYPOTHESES, TESTING hypotheses, and formulating THEORIES that are supported by data.

Observing and collecting data Observing is the USE OF THE SENSES to obtain information. make MEASUREMENTS and COLLECT DATA data may be QUALITATIVE descriptive) QUANTITATIVE (numerical)

Observing and collecting data Object: ______________________ __________________________________

Observing and collecting data A SYSTEM­ is a specific PORTION OF MATTER in a given region of space that has been selected for study during an experiment or observation. observation of a reaction in a test tube the test tube and its contents form a system

Formulating hypotheses Scientists MAKE GENERALIZATIONS (look for RELATIONSHIPS and PATTERNS) based on the data.   Scientists USE GENERALIZATIONS about the data to formulate a HYPOTHESIS, or TESTABLE STATEMENT. hypothesis is the basis for MAKING PREDICTIONS and EXPERIMENTING Hypotheses are often “IF-THEN” statements. the “then” part is a prediction that is the basis for experimenting

Testing hypotheses Testing a hypothesis requires experimentation that provides data to SUPPORT or REFUTE a hypothesis or theory. CONTROLS are the experimental conditions that REMAIN CONSTANT.   VARIABLES are any experimental conditions that CHANGE.

theorizing A MODEL in science is more than a physical object. It is often an EXPLANATION of HOW PHENOMENA and how DATA or EVENTS are related. VISUAL, VERBAL, OR MATHEMATICAL example: ATOMIC MODEL OF MATTER

theorizing A THEORY is a BROAD GENERALIZATION that EXPLAINS a body of facts or phenomena. successful theories predict the results of many new experiments example: ATOMIC THEORY

Stages in the scientific method