survey of chemistry laboratory i chem 1151l blue bottle the hypothesis cycle
TRANSCRIPT
SURVEY OF CHEMISTRY LABORATORY I
CHEM 1151L
BLUE BOTTLETHE HYPOTHESIS CYCLE
CAUTION!!!CAUTION!!!BE SURE TO WEAR SAFETY GLASSES AT
ALLTIMES IN THE LABORATORY
NO EXCEPTIONS TO THIS RULE!
- To access students’ critical thinking skills
- To access students’ ability to communicate in writing
- Students will design and carry out a variety of experiments
to discover the cause(s) of changes observed
BLUE BOTTLE
SOLUTIONS FOR BLUE BOTTLE
- Obtain a clean 125 mL Erlenmeyer flask
MIX SOLUTIONS
Mix in the flask
- 25 mL of solution A
- 25 mL of solution B
- Four drops of solution C
MIX SOLUTIONS
- Place a rubber stopper firmly on the flask
- Shake the contents vigorously
MAKE OBSERVATIONS
- Set the flask down
- Watch for a few minutes
- Record any observations made
MAKE OBSERVATIONS
- Shake the flask again
- Make observations again
MAKE OBSERVATIONS
- List the major goal of this exercise
- Break the major goal into two minor goals that can be investigated
DESIGN EXPERIMENTS
For each of the minor goals
- Write a testable hypothesis
- Design an experiment to test the hypothesis
- Consult instructor for approval
- Carry out the experiment
DESIGN EXPERIMENTS
DESIGN EXPERIMENTS
A number of laboratory materials are available
- Litmus paper
- Ice
- Warm temperature bath
- Nitrogen gas
- Oxygen gas
- Buret
- ETC
For each of the minor goals
- Record observations
- Draw conclusions
- Write a restructured hypothesis
- Repeat the cycle until the goals are accomplished
DESIGN EXPERIMENTS
- Synthesize your conclusions into a coherent explanations of the major goal
DESIGN EXPERIMENTS
Write a formal laboratory report that includes the following elements
- An introduction to the overall goal of the work- A statement of your initial observations
- A statement of the first hypothesis developed- A description of the experiment designed to test the hypothesis
- A clear description of the result of that experiment- The conclusion drawn from the experiment
- Repeat Steps 3 – 6 for each hypothesis developed- An overall summary of all the experiments
- The final conclusion
WRITTEN REPORT