Environmental Final

• How many carbon atoms are in the molecule?

  the number of lines

  (the hydrogen are at the end of each line)
• Hydrobromic acid (HBr) is a strong acid. If sodium bromide (NaBr) is added to water at pH7 and completely dissociates, what will happen to the pH?

  pH will not change
• which of the following is an example of opportunistic pathogen?

  
  

  cholera

  legionella pneumophila

  giardia

  schistosoma

  legionella pneumophila

  
  

  an opportunistic pathogen is a ???????
• at what temperature is water most dense?

  4 °C
• The pKa of 1-propanol (CH3CH2CH2OH) is 16.9. At normal pH range (~6-8), which form can we assume is present at negligible concentration - protonated or deprotonated (CH3CH2CH2O-)?

  protonated

  
  

  bc ?????
• Water is exposed to air and absorbs CO2. Which species will be present at equilibrium?

  
  

  H2CO3

  HCO3^(-1)

  CO3 ^(2-)

  All are possible, depending on pH

  All are possible, depending on pH
• Individuals infected with which of the following pathogens can spread the disease via dormant cysts, but are only 5-10% likely to show symptoms?

  
  

  adenovirus

  norovirus

  vibrio cholera

  giardia

  giardia
• What is the formula for the sulfate anion?

  
• which of the following water pollutants is associated with agriculture?

  
  

  nitrogen

  salts

  phosphorus

  all of these


  all of these
• which of the following parameters is used to quantify the amount of suspended solid particles in water?

  
  

  conductivity

  alkalinity

  particle size distribution

  turbidity

  turbidity
• chemical elements are defined by the atoms containing a certain number of what?

  protons
• which if the following statements apply to endocrine disruptors? (select all that apply)

  
  

  arise primarily from natural sources of contamination

  only found in groundwater

  can interfere with hormone function

  can have toxicological effects even at low concentration

  - can interfere with hormone function

  - can have toxicological effects even at low concentration
• which of the following is regulated by a secondary drinking water standard as part of the Safe drinking water act?

  
  

  total viruses

  taste and odor

  lead

  mercury

  taste and odor
• what is the main goal of coagulation in drinking water treatment

  to neutralize surface charge of colloidal particles
• how do granular media filters remove colloidal particles from water?

  the colloids collide with media particles and stick to them
• contamination from agricultural runoff or road salts are examples of what?

  nonpoint source pollution
• covalent bonding involved sharing of electrons among atoms?

  
  

  true / false

  true
• which of the following contaminants is known to bioaccumulate?

  
  

  total suspended solids

  salts

  phosphorus

  mercury (Hg)

  mercury (Hg)
• toluene, is an example of what type(s) of molecule? select all that apply

  
  

  carbonate

  polyatomic ion

  organic

  aromatic

  organic

  aromatic

  
• primary standards of the Safe Drinking Water Act come in which two forms?

  maximum contaminant levels and treatment techniques
• adjusting the flow ratio between return (RAS) and waste (WAS) lines in the activated sludge process affects which of the following

  
  

  food-to-microbe ratio (F/M)

  ratio of BOD conversion to COs vs biomass

  cell retention time (θc)

  all of these

  all of these
• the conversion of N2 gas to nitrogen-containing nutrients such as nitrate and ammonia is known as

  nitrogen fixaction
• which is a characteristic of combined chlorine disinfection?

  
  

  it leads to fewer byproducts than free chlorine

  involves both addition of free chlorine and ammonia

  it provides a relatively long-lasting residual in the distribution system

  all of these

  all of these
• which of the following is an alternative process to activated sludge for BOD removal?

  membrane bioreactor
• which organism is most resistant to inactivation by chemical oxidants?

  cryptosporidium parvum cysts
• an activated sludge process with high BOD removal ratio, high aeration requirements, and poor settleability of solids is characteristics of what type of cell (solids) retention time?

  high (>6d)
• what role do anaerobic digestors play in wastewater treatment?

  
  

  disinfection of treated wastewater

  ammonia removal prior to activated sludge treatment

  removal of recalcitrant dissolved organic compounds

  none of these

  none of these because they actually ........
• which of the following can be removed from wastewater by precipitating as a solid, followed by sedimentation?

  phosphorus
• what type of reactor can be used to determine the rate constant (k) of a chemical reaction?

  batch reactor
• if only organic compounds are present, with no external electron acceptors such as O2 or SO42-, which type of metabolism could microbes use to obtain energy?


  fermentation
• a water sample is collected from a polluted river and analyzed for BOD5, using the appropriate methods. Which of the following would affect the result

  
  

  
  

  the presence of suspended mineral particles

  the biodegradability of the organic compounds in the water

  the dissolved oxygen concentration in the river at the time it was sampled

  all of these

  the biodegradability of the organic compounds in the water
• why does organic nitrogen contribute minimally to BOD5

  it takes longer than 5 days for bacteria to begin using it as an electron donor
• consider a point source discharging oxygen-demanding wastes into a river. what can affect the distance of the critical point (DO minimum) downstream from the discharge point?

  altitude

  turbulent white water vs nonturbulent flow (turbidity)

  stream velocity
• which of the following is true of heterotrophs?

  - they contribute to oxygen depletion in waters with high BOD

  - they require preexisting organic compounds (reduced carbon)

  - they obtain energy from thermodynamically favorable redox
• a conservative (unreactive) compound is briefly injected into the influent of an ideally-performing plug-flow reactor. which of the plots shows the concentration-time profile that will be observed in the reactor effluent?

  
• what is a first-order rate expression for a chemical degradation reaction?

  dC/dt = -kC
• Consider a lake with high alkalinity that begins to be contaminated by acid rain. what will happen?

  the pH will decrease only slightly at first
• Biological treatment of wastewater using aeration/aerobic conditions followed by anaerobic conditions is a common way to remove what?

  nitrogen compounds
• what is a defining quality of an autotroph


  they obtain carbon for synthesis from CO2
• which is a water disinfectant that inactivates microorganisms by directly causing DNA mutations?

  Ultraviolet radiation