The Scientific Method

Scientific Method The scientific method is a process that is used to find answers to questions about the world around us.

Scientific Method Is there only one “scientific method”? No, there are several versions of the scientific method. Some versions have more steps, while others may have only a few.

Scientific Method However, they all begin with the identification of a problem or a question to be answered based on observations of the world around us. They also provide an organized method for conducting and analyzing an experiment.

Scientific Method What is a hypothesis? It is an educated guess based on observations and your knowledge of the topic.

Scientific Method What is data? It is information gathered during an experiment.

Scientific Method Identify the Problem What do you want to know or explain? Use observations you have made to write a question that addresses the problem or topic you want to investigate.

Scientific Method Form a Hypothesis What do you think will happen? Predict the answer to your question or the outcome of the experiment.

Scientific Method Create an Experiment How will you test your hypothesis? Develop a procedure for a reliable experiment and address safety rules.

Scientific Method The variable that is changed in an experiment is called the independent variable.

Scientific Method The variable that you watch to see how it changes as a result of your changes to the independent variable is called the dependent variable.

Scientific Method When graphing data that is collected, the independent variable is plotted on the x-axis (horizontal axis). The dependent variable goes on the y-axis. 12

Scientific Method Perform an Experiment and Collect Data Follow the steps in your procedure to perform your experiment. Record data and observations!

Scientific Method Analyze the Data Is the data reliable? Do your data and observations from the experiment support your hypothesis?

Scientific Method Is your data inaccurate or the experiment flawed? If YES, modify the experiment. Rewrite your procedure to address the flaws in the original experiment. Perform the modified experiment and analyze the new data.

Scientific Method If the data is reliable, communicate the results. Write a conclusion that summarizes the important parts of your experiment and the results.

Assessment Questions Question Identify the dependent variable and the independent variable in the following experiments.

independent variable: dependent variable: temperature Assessment Questions Question 1 A student tests the ability of a given chemical to dissolve in water at three different temperatures. Answer independent variable: dependent variable: temperature ability to dissolve in water

independent variable: dependent variable: Assessment Questions Question 2 A farmer compares how his crops grow with and without phosphorous fertilizers. Answer independent variable: dependent variable: presence of phosphorous fertilizer crop growth