Hey, Can you answer questions 5,6,7, and 8 for me. The subject is environmental
ID: 1713251 • Letter: H
Question
Hey, Can you answer questions 5,6,7, and 8 for me. The subject is environmental Engineering. Thank You!
I. Answer following questions (each question is worth 2 pts, total 16 pts): I. What have you learned from DO/BOD experiment? 2. Why, do you think we could proceed with BOD without dilution for those particular water samples you got? 3. What would happen if we would go ahead and dilute your water sample? 4. Deseribe what seeded water is, and why we don't need a seed for this experiment? Or maybe we do need to seed them? Which one 5. W hat is a minimum concentration of oxygen that has to remain in water after 5 or 7 days? Why do we need to have a limit for minimum DO in water? 6. What to do if initial DO is low? 7. When bubble of oxygen will be introduced to bottle after measuring initial DO, and this bubble will stay for the 5 days, what reading you expected to have for 5-days DO: higher than supposed be, lower than supposed to be, or it should not matter? Please justify your answer. When you compare your results for tap or distilled water with pond water, what your BOD, says about loading of organics in tested water? Justify your answer 8. Solve problems 5,5, and 5.9. In addition, use diagram from problem 5.6 and find: L·Li, Lo and BOD2 and BOD (total 9 pts).Explanation / Answer
Ans5. There should be minimum of 1-2 mg/l of DO in water after 5-6 days because if the DO is below this value then it shows that the sample had more requirement of oxygen for the decomposition of the organic material but due to absence of DO we couldn't find it, hence if such case occurs we need to discard our readings and start the experiment again.
Ans6. If Initial DO is low then we have dilute the sample using seeded BOD water so that there is sufficient DO for the experiment.
Ans7. Introduction of bubble is also a way to increase the DO of the sample. It will show a value of DO more than without the bubble as it is true that is doesn't matter as we are getting the correct reading of BOD because of introduction of bubble.
ANS8. Now on comparing the results with tap water or distilled water obviously the BOD of the sample would be higher because the organics present would be nill in distilled water, But on comparison with the lake it depends whether from where the sample is being taken.