a. I) describe how microorganisms transform nitrogen during wastewater treatment ii? give examples of the microorganism(species, functional groups) involved in nitrogen transformation reaction

Ammonia gas is being absorbed by water in a wetted-wall column. At one level of the column, the following data applies: 
gas-phase mass transfer coefficient 5.22 × 10–9 kmol m–2 s–1 Pa–1 
liquid-phase mass transfer coefficient 3.88 × 10–5 m s–1 
Henry's constant 0.955 kPa (kmol m–3)–1. mole fraction of ammonia in liquid* 1.351 × 10–3 mole fraction of ammonia in gas* 0.065 
total pressure of system 1.013 bar 
mole mass of ammonia 17 
*Note: these values will need to be converted to concentrations in kmol m–3.

(a) What is the partial pressure of the ammonia gas at the gas/liquid interface?

(b) What is the molar concentration of the ammonia in the liquid at the interface?

A piece of equipment having a negligible salvage and scrap value if estimated to have a MACRS and straight line recovery period of 5 years. The original cost of ther equipment was $500,000. Determin the depreciation charge of the euipment for the second yeqr if straight line depreciation is used and the percentage of the original investment paid off in the first 2 years.

Compare the differences in viscosity and density of water (SG = 1) and gasoline (SG = 0.803). Determine the pressure at the bottom of a 8m high tank that is filled with water, and compare it to the pressure at the bottom if the tank is filled with gasoline. Calculate the volumetric and mass flow rates of the two fluids in a 0.10m diameter pipe moving at a velocity of 4.2 m/s.

a) Give examples of 2 different biomonitoring approaches that could be used to assess the toxicity of a water source b) Define what WET tests are and how you wold apply them for the biomonitoring of a water body c) Discuss the difference between the olfactory and chemical analysis for the assessment of odorous emissions

Water treatment plants are increasingly employing online turbidity monitoring a) Explain why turbidity monitoring can be an important measurement form a public health perspective b) How would you use the results of online turbidity monitoring to help ensure safe drinking water quality?

1) What characteristics of a compound lead to solubility in water? Name as many as you can and explain them.
2) What characteristics of a compound lead to insolubility in water? Name as many as you can and explain them.
3) Are ionic compounds (anions or carboxylic acids or ammonium salts of amines) more or less soluble in water that the corresponding neutral compound? Explain.
4) Some of the most important functional groups in organic chemistry are alkane (actually a lack of other functional groups), alcohol, phenol, ether, amine, ketone, carboxylic acid, ester, and amide. Draw a simple example of each of these and show how it hydrogen bonds with water. If it can't hydrogen bond, so state.
5) Which of the functional groups listed in Question 4 is an acid in water (i.e., would be more soluble in base)? Which of them can be a base (i.e., would be more soluble in acid)?

The variation of the spectral transmissivity of a 0.6cm thick glass window is 0.92 in the wavelength range from 0.3-3micrometer. Determine the average transmissvity of this window for solar radiation at T=5800K. Also, determine the amount of solar radiation transmitted through the window for incident solar radiation of 650W/m².

1- Consider the following substances: a polar solute and polar solvent. Explain the interactions of these and whether a solution will form. • H1 or HLE of Solute:

• H2 HLE of Solvent:

• H3 or HHYD:

• HSolution: Outcome

Options: a-Highly Endothermic b-Slightly Endothermic c- Highly Exothermic d-Slightly Exothermic

2- Consider the following compounds. Which is insoluble?

• VI2VI2

• HgBr2HgBr2

• NaBr

• NaCl

• All of these

• None of these

3- Select the conditions where liquid solutes have the highest solubility in water. Select those that USUALLY apply.

• Structural effects: The molecule should be .

• Agitation: Agitating the solution the solubility.

• Pressure: Solubility is highest when pressure is .

4- Ethanol has a Kb of 1.22 °C/m and usually boils at 78.4 °C. How many mol of an nonionizing solute would need to be added to 45.37 g ethanol in order to raise the boiling point to 82.8.

5- Water has a Kf of -1.86 °C/m. Calculate the new freezing point of an aqueous solution made by mixing 37.81 g water and 2.85 g MgCl2.

6- A solution contains 15.03 grams of NaCl in 0.557 kg water at 25 °C. What is the vapor pressure of the solution? (The vapor pressure of pure water is 23.7 torr at 25 °C.)

7- When a colloid separates by droplets becoming progressively bigger until they settle out it is called ________.

• flocculation

• coalescence

• creaming

8- When a colloid separates by one of the substances migrating to the top of the mixture it is called ________.

• coalescence

• flocculation

• creaming

9- How many mL of a 5 M HCl solution would it take to make a 250 mL of a 1.6 M solution? Give your answer to 1 decimal space.

10- What is the concentration of magnesium bromide, in ppm, if 55.3 g MgBr2 is dissolved in 9.24 L water. Record your answer in scientific notation to 3 significant figures.

11- How many mL of a 6.8 M HCl solution would it take to make a 250 mL of a 1.6 M solution?

• 0

• 0.4

• 1062.5

• 58.82

• 0.24

An 8" ID pipe carries air at 80.0 ft/sec, 21.5 psi absolute and 80°F. How many pounds of air are flowing? The 8" pipe reduces to a 4" ID pipe and the pressure and temperature in the 4" pipe are 19.0 psi absolute and 48°F respectively. Find the velocity in the 4" pipe and compare the flows in ft3/sec in the two pipes.

LMTD of a cross-flow heat exchanger is

How does a photovoltaic cell generate electricity? How thick is the depletion width in a silicon solar cell? How can you calculate it?

What are nanostructured materials in a PEM Fuel Cell?

Identify the anode in a galvanic cell of copper and brass electrodes in standard solutions of their own ions. Identify the anode in a galvanic cell of a two-phase microstructure of a 50:50 Pb-Sn alloy. Identify the anode in a galvanic cell of a lead-tin solder on a Cast iron in seawater. Identify the anode in a galvanic cell of a brass bolt in a passive 430 stainless steel plate in seawater.