Question

Introduction to environmental

(4-1, DC 332) Glutamic acid (C₅H₉O₄N) is used as one of the reagents for a standard to check the BOD test. Determine the theoretical oxygen demand of 150 mg/L of glutamic acid. Assume the following reactions apply:

C₅H₉O₄N + 4.5O₂ →5CO₂ + 3H₂O + NH₃

NH₃ + 2O₂ → NO₃^- + H⁺ + H₂O

2. (4-3, DC 332) If the BOD₅ of a waste is 220 mg/L and the ultimate BOD is 320 mg/L, what is the rate constant (base 10)?
3. (4-5, DC 332) Convert the rate constant found in problem 2 to base e.
4. (4-7, DC 332) Assuming that the data in problem 2 were taken at 20 ^oC, compute the rate constant at temperature of 15 ^oC.
5. (4-15, DC 333) Using the Thomas Method, calculate the BOD rate constant ((in base e) from the following data:

t, day	2	5	10	20	35
BOD, mg/L	86	169	236	273	279.55

6. Solids: The laboratory analysis of 25 mL sample after filtration gave the following data:

• Weight of the filter disk after drying at 103 ^oC and 550 ^oC = 5.31g
• Weight of the filter disk and sample after drying at 103 ^oC = 5.374g
• Weight of the filter disk and sample after igniting at 550 ^oC = 5.339g

Determine the concentrations (in mg/L) of: a) Total suspended solids (TSS), b) Volatile suspended solids (VSS), and c) Fixed suspended solids (FSS) of the water sample.

Answer 1