The Scientific Method Science Scientific Method 1a. A way of exploring the natural world in a systematic (orderly) way. 2a. The process of systematic exploration.

The Scientific Method 3. Scientific Method Procedures 3a. Observing and asking questions. 3b. Forming hypotheses 3c. Conducting controlled experiments 3d. Collecting and analyzing data 3e. Drawing conclusions

The Scientific Method 4. Observation 4a.How a scientific investigation begins. Example: Students who study seem to have better test scores.

The Scientific Method 5. Hypothesis 5a. A scientific explanation for observations. 5b. It must be testable. 5c. It can be accepted or rejected Example: If students study at least 3 nights a week, then they will have better test scores.

The Scientific Method 7. Controlled Experiment. 7a. A hypothesis should be tested by changing only one variable. 7b. All other variables should be kept unchanged, or controlled.

The Scientific Method 8. Independent Variable (IV) 8a. Aka manipulated variable. 8b. The variable that is deliberately changed Example: The amount of time a student studies.

The Scientific Method 9. Dependent Variable (DV) 9a. The variable that is observed. 9b. It changes in response to the independent variable. Example: The students test scores.

Practice 1 -Observation: Chocolate may cause a sick stomach. -Independent Variable: -Dependent Variable: -Hypothesis:

Practice 2 Observation: Bacterial growth may be affected by temperature. Independent Variable: Dependent Variable: Hypothesis:

The Scientific Method (part 2) 10. Experimental Group (EG) 11. Control Group (CG) 10a. Part of an experiment where only one variable is changed 11a. Part of an experiment that is not changed at all. 11b. Used for comparison

Practice 3 Experimental Question: What is the effect of boiling water on the growth rate of plants? Experimental Group:___________________________ Control Group: _______________________________ IV: _________________________________________ DV:_________________________________________ Hypothesis: __________________________________ ____________________________________________

Graphs and Tables Line Graphs (continued) 1d. When multiple factors are involved, they can both be plotted on the same graph using more than one line.

Practice 1 Referring to the multiple line graph above, identify the IV and the DV. IV:________________________________________ DV________________________________________ What is the best prediction of the solubility of salt W at 100°C? ______________________________________________

Graphs and Tables 2. Bar Graphs 2a. Good for comparing data about similar things.

Practice 2 Referring to the bar graph above, describe how the presence of fungus generally affects the growth of the trees.___________________________________________ ________________________________________________ Which tree shows the greatest difference in growth if the fungus is present?______________________

Graphs and Tables 3. Tables 3a. Also called a chart 3b. Useful for organizing and presenting numerical data.