Scientific Processes in Grade 8 Science Lab Report

1. Unit 1 Scientific Processes Grade 8 Science ~ Mrs. Paolini

2. Grade 8 Science Lab Report 101 The student will plan and conduct investigations in which: • observations of living organisms are recorded in the lab and in the field; • hypotheses are formulated based on direct observations and information from scientific literature; • variables are defined and investigations are designed to test hypotheses; • graphing and arithmetic calculations are used as tools in data analysis; • conclusions are formed based on recorded quantitative and qualitative data;

3. The student will plan and conduct investigations in which: • sources of error inherent in experimental design are identified and discussed; • chemicals and equipment are used in a safe manner; • appropriate tools, are used for gathering and analyzing data and communicating results; • research utilizes scientific literature; • alternative scientific explanations and models are recognized and analyzed; and • a scientific viewpoint is constructed and defended (the nature of science).

4. Scientific Processes Vocabulary • Observation-the act of observing (touch, taste, smell, feel, see, etc.) • Inference-a quick conclusion that attempts to explain an observation • Prediction- to forecast; to guess the outcome of a situation beforehand • Analysis-to separate or break apart into smaller sections for study

5. Hypothesis Scientific Method Vocabulary • Conclusion- to close or bring to an end; to accept or reject a hypothesis in an experiment • Data-recorded observations or measurements • Hypothesis-a tentative explanation that accounts for a set of facts & that can be tested by further investigation

6. Scientific Method Vocabulary • Controlled Experiment- an experiment in which all variables except the ONE being tested are identical in order to make the experiment fair & the results reliable • Variable- any factor in an experiment that could affect the results & is therefore tested separately

7. Scientific Method Vocabulary • Controlled Variable- a variable that is not changed • Independent Variable –a variable that you purposely manipulate (manipulated variable) • Dependent Variable-the variable being observed that changes in response to the independent variable (responding variable)

8. Scientific Method Vocabulary • Quantitative Data- data that involves numbers or measurement usually in the form of a chart or graph • Qualitative Data- anecdotal or descriptive data that does NOT involve numbers or measurement

9. Scientific Method Vocabulary • Operational definition - a statement that describes how a particular variable is to be measured, or how an object or condition is to be recognized dependent variable

10. Example of an Operational Definition When you finish working on an experiment, wash your hands thoroughly. What does thoroughly mean? • With soap and water • 20-30 seconds (sing Happy Birthday) • Rub palms, back of hands, in between fingers, thumbs and nails

11. Progression of Ideas in Science • Hypothesis- a possible explanation to a question based on information the scientist has already gathered - If experiments show a hypothesis to be correct, other scientists may accept it as support for a scientific theory. EX: Plants obtain their energy from the Sun.

12. Progression of Ideas in Science • Scientific Theory- a general statement of why things work based on hypotheses that have been tested many times

13. Progression of Ideas in Science - Theories are used to explain & predict the outcome of other experiments - Theories must be tested - Sometimes they are wrong & must be modified or discarded EX: The Earth is flat.

15. Progression of Ideas in Science • Scientific Law- a statement of what happens in a certain event based on verified observations & experiments

16. Progression of Ideas in Science - Summaries of the results of many, many experiments & observations - When results of a series of experiments are the same each time they no longer need to be tested EX: Newton’s Law of Gravity

18. Progression of Ideas in Science • Which one is most likely to be wrong- hypothesis, theory, or law? 1. 2. 3. Hypothesis Theory Law

19. The Scientific Method • An organized way to solve a problem through experimentation & observation.

20. The 6 Steps of the Scientific Method* * In real life, these are not always done in order…but when writing a lab report, they are!

21. 1. State the Problem • Form a question about a specific event or reaction EX: Mouthwash kills bacteria. Which brand works best?

22. 2. Collect Information • Research the problem EX: Read the labels of 3 common brands of mouthwash and see which has the most antiseptic (germ-killing) ingredients. The amount of antiseptic ingredients would be the one that works the best. Operational definition

23. 3. Form a hypothesis • Make an educated guess based on your research. A hypothesis can be recognized by an “if, then” statement. EX: If Listerine has more antiseptic ingredients than Scope or Wal-Mart brand, then it will kill more bacteria.

24. 4. Design an Experiment • Devise a way to test your hypothesis. Create a CONTROLLED experiment.

25. A controlled experiment MUST have 2 groups. CONTROL GROUP: all conditions remain the same EXPERIMENTAL GROUP: only the condition that you are testing for is changed ONLY 1 condition is changed!

26. Establish the variables for your experiment. INDEPENDENT VARIABLE: the variable that is changed, manipulated (X axis for graphing) DEPENDENT VARIABLE: the change caused by the manipulation of the independent variable (Y axis for graphing)

27. Mouthwash Experiment Control Group -no mouthwash Petri dish Bacteria grown from swab Listerine Experimental Group Scope Wal-Mart brand

28. Mouthwash Experiment INDEPENDENT VARIABLE: Type of Mouthwash DEPENDENT VARIABLE: Amount of bacteria killed

29. 5. Collect & Analyze Data • Run the experiment & document the data

30. 2 Types of Data QUANTITATIVE: numerical data, deals with specific quantities, usually in the form of a graph or chart QUALITATIVE: descriptive data, describes how something looks, smells, sounds, or feels; deals with qualities

31. QUALITATIVE EX: The control group and the Wal-Mart brand have a strong smell; the Listerine & Scope don’t smell as bad. QUANITATIVE EX: Area of Inhibition for Mouthwash Brands

32. 6. Draw Conclusions • Determine from the data collected if the hypothesis was correct or incorrect EX: Listerine did kill more bacteria than the other brands because it had more antiseptic ingredients.

33. This is what it looks like in class…

35. This is what it’s like in the real world…