SURVEY OF CHEMISTRY LABORATORY I CHEM 1151L BLUE BOTTLE THE HYPOTHESIS CYCLE

CAUTION!!! BE SURE TO WEAR SAFETY GLASSES AT ALL TIMES IN THE LABORATORY NO EXCEPTIONS TO THIS RULE!

BLUE BOTTLE - 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

SOLUTIONS FOR BLUE BOTTLE

- Obtain a clean 125 mL Erlenmeyer flask MIX SOLUTIONS - Obtain a clean 125 mL Erlenmeyer flask

- Four drops of solution C MIX SOLUTIONS Mix in the flask - 25 mL of solution A - 25 mL of solution B - Four drops of solution C

MAKE OBSERVATIONS - 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 again - Shake the flask again - Make observations again

DESIGN EXPERIMENTS - 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

A number of laboratory materials are available 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 DESIGN EXPERIMENTS 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

WRITTEN REPORT 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