The acquirement of scientific knowledge

1. The acquirement of scientific knowledge Aka the scientific method

2. What is The Scientific Method? • Defined as an organized, logical approach to solve a problem or question

3. Steps of the Scientific Method • Define a Problem or Ask a Question • A clear statement of the problem or question is a crucial step in beginning an investigation

4. Steps of the Scientific Method • Make Observations • Use of all or some of the senses (sight, taste, feel, hearing, or smell) • Called a qualitative observation • Make a measurement • Called a quantitative observation

5. Steps of the Scientific Method • Formulate a Hypothesis • Predict a possible answer to the problem or question • It should be based on facts and observations • Should be capable of testing

6. Steps of the Scientific Method • Designing and Performing an Experiment • Develop and follow a procedure • Include a detailed materials list • The outcome must be measurable (quantifiable) • Experiment must be controlled and include independent and dependent variables! • Experimental evidence will either support or contradict hypothesis

7. Independent variable(The Cause) • The independent, or manipulated variable, is a factor that’s intentionally varied by the experimenter • Goes after the “If” in your hypothesis!

8. Dependent variable(The effect) • The dependent, or responding variable, is the factor that may change as a result of changes made in the independent variable • Goes after the “Then” in your hypothesis!

9. Control group • In a scientific experiment, the control is the group that serves as the standard of comparison • The control group may be a “no treatment" or an “experimenter selected” group

10. Control group • The control group is exposed to the same conditions as the experimental group, except for the variable being tested All experiments should have a control group!

11. Steps of the Scientific Method • Collect and Analyze Results • Data, such as observations and measurements, are recorded and then analyzed • Confirm the results by retesting • Put your data into a data table • Make the data table into a graph • Graphs make it easier to see patterns in the data! • DRY MIX • Dependent variable = Responding variable = Y-axis • Manipulated variable = Independent variable = X-axis • If the data support the hypothesis, then the conclusion would state that the hypothesis is supported • If the data contradict the hypothesis, then a new hypothesis must be made and tested

12. Steps of the Scientific Method • Draw a Conclusion • Scientists base their conclusions on observations made during experimentation • Include a statement that accepts or rejects the hypothesis • A hypothesis is NEVER correct or incorrect • Make recommendations for further study and possible improvements to the procedure

13. In Summary… • Careful observation and collection of data is the foundation of any experiment • Observations must be reproducible and may be categorized as: • Qualitative • Descriptive, e.g., blue • Quantitative • Measureable, e.g., 4.0 cm • What is an inference? • An inference is an explanation or assumption of what is observed • These are conclusions and may change as more data is collected

14. Time for the candle demo • Watch closely and list as many observations as you can on page 14 of your notebook! • Then, identify each observation as quantitative, qualitative, or an inference • A table like the one below may be useful in organizing your thoughts:

15. Whoa!! • Did any of your earlier observations change after your last observation (eating the candle)? • How does this relate to what we discussed about the scientific method?

16. Your turn! • Time to apply the scientific method with the Gum Lab!