If two separate 100 mL samples of waste water were collected. The first was aerated also seeded with bacteria. It was then fixed utilizing the Winkler method and titrated using a 0.0125 M sodium thiosulfate solution to a starch-iodide endpoint after addition of 7.18 mL of the sodium thiosulfate solution. The second sample was sealed as well as stored in a dark 40°C cabinet for 20 days. After 20 days, the sample was fixed utilizing the Winkler method and titrated using a 0.0125 M sodium thiosulfate solution to a starch-iodide endpoint after addition of 6.26 mL of the sodium thiosulfate solution.
Define what is the BOD20 and the ultimate BOD? What should the BOD5 have been?