Environmental Sampling

  1. Which type of sampling has the largest bias?
  2. Which type of sampling is the most expensive?
    Random (requires largest number of samples)
  3. Which type of sampling has the smallest bias?
  4. What sampling plan would you use when the population is relatively homogeneous?
  5. Which sampling plan requires knowledge of the site?
  6. Which sampling plan is the most efficient or cost effective?
  7. Air and stack emission sampling requires ______ volumes of sample
    large (concentrations are usually low)
  8. For small ponds you would like collect a ______ while for large ponds you may want to collect at different _____ because of temperature differences
    • composite sample
    • depths
  9. What are two main types of interferences?
    • Spectral
    • Non spectral
  10. Give an example of a non spectral interference
    Matrix - something else bonds to the analyte so it is not detected
  11. Give an example of a spectral interference
    Polyatomic interference (2 atoms whose combined mass is the same as another atom/atoms so that you cannot distinguish them)
  12. A type of sample-taking technique that is fast but not necessarily representative
    Grab Sampling
  13. Name 3 ways to deal with matrix interferences
    • Add a releasing agent
    • Matrix match standards and blanks
    • Use standard addition
  14. If get a false positive or false negative test result, what should you do?
    Repeat the analysis
  15. Name 3 types of blanks
    • Equipment Blank
    • Field Blank
    • Trip Blanks
  16. Which two types of blanks are prepared in the field?
    • Equipment
    • Field
  17. Which type of blank is prepared before going to the field?
    Trip blank
  18. It is usually better to analyze in the field if...
    • the parameter could change during transport
    • you need results immediately
    • the equipment is easier to transport than the sample
Card Set
Environmental Sampling
From notes and Module 9 powerpoint