1 The Scientific Method

By experimentation we gather firm evidence or results that we can use to either prove or disprove thehypothesis.RESULTS:Substance to TestBubbles formed?YesNoWound with fresh bloodWound with dried bloodHealthy skinWoodCut raw potatoCut raw onionAluminum foilPlatinumExperiments must provide enough evidence to eventually allow reasonable conclusions about whetheror not the initial hypothesis was correct. Often multiple experiments must be performed to be certain thatthe results are repeatable. Sometimes the hypothesis must be revised and then tested repeatedly untilconfident conclusions can be made. Notice the modifications in the following:CONCLUSION:Hydrogen peroxide will form bubbles whenever blood is present but blood is not essential for bubbleformation.RATIONALE:My experiment showed that hydrogen peroxide forms bubbles when dropped on either fresh or driedblood but also forms bubbles when in contact with raw potato, raw onion, and platinum metalwhich do not contain blood.When designing any experiment the potential for errors must be taken into account. Errors occurwhenever any kind of measurement is made as well as when sloppy technique is used. It is impossible toavoid all errors. Each error must be recognized and considered whenever conclusions are made.ERROR ANALYSIS:Although all tests were done at room temperature (25 o C) the bloody wounds andhealthy skin were at body temperature (37 o C). To avoid this difference perhaps one ormore of the following modifications could be made: a drop of blood at room temperature could be dropped into a sample ofperoxide at room temperature. a sliver of dead skin at room temperature could be used instead of skin on aliving body. Other samples could be brought up to 37 o C before being tested with theperoxide.Often, when we do research to answer one question, many more questions arise. One experiment cantherefore lead to many more. Examples of Further Questions that arise from our peroxide experimentcould be:FURTHER QUESTIONS: What is the substance in blood that causes hydrogen peroxide to bubble? Do raw potato and raw onion contain the same substance that is present inblood? Would a cooked potato cause hydrogen peroxide to bubble?XXXXXXXX8CH104 Lab 1: The Scientific Method (F14)