220 likes | 242 Views
TEK 8.2. Scientific processes The student uses scientific inquiry methods during field and laboratory investigations. Student Expectations.
E N D
TEK 8.2 Scientific processes The student uses scientific inquiry methods during field and laboratory investigations.
Student Expectations • Plan and implement investigative procedures including asking questions, formulating testable hypotheses, and selecting and using equipment and technology • Collect data by observing and measuring • Organize, analyze, evaluate, make inferences, and predict trends from direct and indirect evidence • Communicate valid conclusions • Construct graphs, tables, maps, and charts using tools including computers to organize, examine, and evaluate data
Scientific Method A series of planned steps used to answer questions and to solve problems • Used in any science experiment or project. • Used everyday since you were born.
Question Observation Inference Hypothesis Experiment Results Analysis Conclusion Queens Offer Indians Help Eating Raspberries And Cherries 8 Steps of the Scientific Method
Scientific Method Question Observation Inference Hypothesis Experiment Results Analysis Conclusion What do you want to know? Use 5 senses (6 senses for girls) Prior knowledge If/then/because statement Test/Procedures Data Organize data (graph) What did you find out?
Question Do different concentrations of H2O2 (Hydrogen Peroxide) affect the chemical reaction with yeast?
Materials • I packet of Yeast • 3% H2O2 (Hydrogen Peroxide) • 30% H2O2 (Hydrogen Peroxide) • Liquid Dish Soap • Food Coloring • Erlenmeyer Flask
Observation… • H2O2 is toxic • H2O2 is a colorless liquid • Dish soap is liquid and creates bubbles Inference…. H2O2 will create a chemical reaction when in contact with other chemicals 30% H2O2 is a stronger solution than 3%
Hypothesis If 30% H2O2 (Hydrogen Peroxide) is mixed with yeast then it will create a greater reaction because it has a stronger/higher concentration.
Experiment Control -A standard for comparison in an experiment. -all the components that are kept the same. Variable A changeable factor in a controlled investigation. -Only one variable should be tested at a time during an experiment!
2 Types of Variables • Independent Variables -the variable we change 2. Dependent Variables -the thing being measured
Identify Variables Independent: What are we changing/testing? The different concentrations of H2O2 Dependent: what are we measuring? The size/rate of the chemical reaction
Controls for ExperimentThe things that MUST remain the same for your experiment to be valid 1. The amount of liquids 2. The container used 3. The brand of the yeast/H2O2 4.environment/temperature/time and date
Experiment/Procedures 1. Pour 1/2 cup of 3% hydrogen peroxide into flask2. Squeeze about 1 table spoon of dish soap into the flask and mix with hydrogen peroxide3. Squeeze 3 drops of food coloring into the flask 4. Open packet of yeast and pour into cup labeled "use for mixing yeast" 5. Pour about 3-5 table spoons of water into the cup with yeast and mix 6. Quickly but carefully pour yeast mix into the flask and observe ( you will time from the time you pour in the mix to the time it takes the foam to reach the very top of the flask)7. Record your results 8. Repeat steps 1-8 for 40 volume hydrogen peroxide
Making Graphs -Use a straight edge -Title the Graph -Include values of pie slices or bars -Color -Label your axis.
DRY/MIX D ependent R esults Y -axis I M X ndependent odify -axis
Conclusion-Paragraph Form3rd person What does the data tell us (Results)? Was the hypothesis correct? Were any mistakes made? How could we change the experiment in the future? How can we apply this to real life?
Conclusion After conducting the investigation, it was evident that different concentrations of H2O2 did affect the rate of the chemical reaction. The hypothesis was correct because the 30% H2O2 had a faster time than the 3%. There were no mistakes made. In the future, the variables could be changed to test different amounts of yeast. This project could create awareness about the dangers of highly concentrated peroxides and how easily accessible they are.
Introduction Checklist • Written in paragraph form • 3rd Person (The student…NO I, my, our, we, etc.) • Question • Inferences/Research • Hypothesis • Independent Variable • Dependent Variable