Chapter 2 Preview Objectives Scientific Method Observing and Collecting Data Formulating Hypotheses Testing Hypotheses Theorizing

Chapter 2 Vocabulary 1. scientific method 2. system 3. hypothesis 4. model 5. theory

Chapter 2 Objectives Describe the purpose of the scientific method. Section 1 Scientific Method Chapter 2 Objectives Describe the purpose of the scientific method. Distinguish between qualitative and quantitative observations. Describe the differences between hypotheses, theories, and models.

Chapter 2 Scientific Method Section 1 Scientific Method Chapter 2 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 Section 1 Scientific Method Chapter 2 Observing and Collecting Data Observing is the use of the senses to obtain information. data may be qualitative (descriptive) quantitative (numerical) 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.

Formulating Hypotheses Section 1 Scientific Method Chapter 2 Formulating Hypotheses Scientists make generalizations based on the data. Scientists use generalizations about the data to formulate a hypothesis, or testable statement. Hypotheses are often “if-then” statements.

Chapter 2 Formulating Hypotheses Section 1 Scientific Method Chapter 2 Formulating Hypotheses A graph of data can show relationships between variables.. what relationship is shown by graph below? Finish this hypothesis.. If phosphorus stimulates corn-plant growth, then…? the effect of phosphorus fertilizer compounds on plant growth

Chapter 2 Testing Hypotheses Section 1 Scientific Method Chapter 2 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.

Chapter 2 Formulating Hypotheses What group is the control group? Section 1 Scientific Method Chapter 2 Formulating Hypotheses What group is the control group? the group given no fertilizer

Section 1 Scientific Method Chapter 2 Theorizing A model in science is more than a physical object; it is often an explanation of how phenomena occur and how data or events are related. visual, verbal, or mathematical example: atomic model of matter A theory is a broad generalization that explains a body of facts or phenomena. example: atomic theory

Section 1 Scientific Method Chapter 2 Scientific Method

An Experimental Approach In the 1500s, a shift started from alchemy to science – King Charles II was a supporter of the sciences “Royal Society of London for the Promotion of Natural Knowledge” Encouraged scientists to use more experimental evidence, and not philosophical debates

Oxygen was required! Lavoisier In the late 1700s, Antoine Lavoisier helped transform chemistry from a science of observation to the science of measurement – still used today He settled a long-standing debate about burning, which was… Oxygen was required!

The Scientific Method A logical approach to solving problems or answering questions. Starts with observation- noting and recording information and facts hypothesis- a proposed explanation for the observation; must be tested by an experiment

A. Steps in the Scientific Method 1. Observing (uses your senses) a) quantitative involves numbers = 95oF b) qualitative is word description = hot 2. Formulating hypotheses (ideas) - possible explanation or “educated” guess 3. Testing (Performing experiments) - gathers new information to help decide whether the hypothesis is valid

A. Steps in the Scientific Method 4. Theorizing constructing models 5. Publish Results - communicating results in journals, magazines, media, online forums, etc.

B. Parts of an Experiment Problem question to be answered 2. Hypothesis proposed answer, educated guess, testable idea 3. Procedure Steps of the experiment 4. Observations data gathered from senses, measurements qualitative and quantitative 5. Conclusions answer based on data, theorizing

Scientific Method We deal with variables, or factors that can change. Two types: 1) Manipulated variable (or independent variable) is the one that we change 2) Responding variable (or dependent variable) is the one observed during the experiment For results to be accepted, the experiment needs to always produce the same result

Using your senses to obtain information Hypothesis is a proposed explanation; should be based on previous knowledge; an “educated” guess The procedure that is used to test the hypothesis A well-tested explanation for the observations; cannot be proven due to new discoveries Tells what happened

End of Section 1 Show 2.1 Practice Problems: Identify the Controls and Variables (Simpsons) Challenge: Scientific Method and Experimenting Video: Sir Alexander Fleming and Penicillin https://www.youtube.com/watch?v=DBlI1p9q6xc&t=144s&index=2&list=PLeITmQhe2X6UvQDwkwMVtjg_oSPRmYsnV