# Lab ReportAnswer the questions below. When you arefinished,

Lab ReportAnswer the questions below. When you arefinished, submit this assignment to your teacher by the due date for fullcredit.Record the number of drops of Reagent D needed to turn the solutionlight blue in each phase of the lab:Set-UpObservationsPhaseAmountof watermL or dropsAmountof yeast16 mL 0.25mL26 mL0.25mL36 mL0.25mL1. Completethe data table.Answer:Experiment ObservationsPhase1Phase2Phase3O2 concentration in ppm (parts per million)= number of drops of Reagent D added to reach blue color (oxygen completelydepleted) and observations2. RegardingPhases 2 or 3 of the experiment, if more or fewer drops of Reagent D (sodiumhydroxide) were needed to get the same blue color as in Phase 1, what does thistell us about the quality of the water when yeast was consuming nutrients inthe water? Did something similar to eutrophication occur?Answer:3. Whatwould happen to the dissolved oxygen in the Missouri River if large amounts ofwaste were dumped into it?Answer:4. Underfavorable conditions, bacteria can multiply every 20 minutes. Starting with onebacteria cell, how many bacteria should you expect after 15 hours? Hint: Under favorable conditions, ifone bacterium becomes 2 in 20 minutes (1 multiplied by 2), those 2 become 4 inthe next 20 minutes, and then those 4 become 8 in the next 20 minutes.That means that 8 bacteria resulted in 1 hour. Now calculate the growth ofbacteria for 15 hours.Answer:5. Inthis lab, you continued to add Reagent D to each solution until it turned blue.The purpose was to remove the oxygen to measure how much was left. The moredrops you had to add to acquire the blue color, the more oxygen was present inthe tube. In which phase(s) did the solution turn blue before you added Reagent D? What do you think that means?Answer:Further Uses6. Nowthat you’ve seen how decomposition affects the amount of dissolved oxygen,collect three samples from somewhere in your house or community. You can getwater from a puddle, a drinking fountain, a stagnant bowl of pet water, astream, a pond, or fresh rainwater—be creative. Then, see how much dissolvedoxygen you find in the sample.Answer:SampleLocationSignsof Decomposition(List any visible microorganisms that might indicate decomposition.)Prediction for DissolvedOxygen LevelResults for DissolvedOxygenYourConclusion(Would this location support aquatic life?)123