Lab Report Water analysis (BoD, MPN and fitration) 24 points) Remember that your
ID: 270764 • Letter: L
Question
Lab Report Water analysis (BoD, MPN and fitration) 24 points) Remember that your lab instructor knows about the bacterial concentration of your water sample. And you are going to get full points only if your results are consistent with the known number(s). Justification will probably be necessary when unexpected results are obtained. I. Biological Oxygen Demand (BOD) (6 points) (1) (3 points) Fill in Table 1 below Table 1. BOD determination of your water sample Volume of sample BOD Volume of water Thiosulfate Thiosulfate added To added Ts aas 75mb a.mba.mk .91 m (2) Analysis (3 point) Were you able to measure the BOD of your sample? If so, discuss teelnc of pollution in the water sample. If not, discuss what might have happened. II. Most Probable Number of Bacteria (MPN) (11 points)Explanation / Answer
Answer: Answer: BOD is the capacity of microorganisms to use the dissolved oxygen (DO) to breakdown the organic compound present in the water sample. The dissolved oxygen rate changes over time and that we are here to calculate from the given data.
It is calculated by simple subtraction between [Initial DO - Final DO/ sample volume] * the volume of the bottle,
In this particular case we find all other values except the volume of the bottle. Then let us simply identify the bottle volume by adding the sample volume (225m) + water volume (75ml), which measure up to 300 ml.
Then fir the numbers in the formula, [Initial DO - Final DO/ sample volume] * the volume of the bottle,
{2.7 ml - 2.1ml/ 225 ml} * 300ml = {0.6/225} *300 = 0.8 ml/L.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.