Which type of sampling has the largest bias?
Which type of sampling is the most expensive?
Random (requires largest number of samples)
Which type of sampling has the smallest bias?
What sampling plan would you use when the population is relatively homogeneous?
Which sampling plan requires knowledge of the site?
Which sampling plan is the most efficient or cost effective?
Air and stack emission sampling requires ______ volumes of sample
large (concentrations are usually low)
For small ponds you would like collect a ______ while for large ponds you may want to collect at different _____ because of temperature differences
What are two main types of interferences?
Give an example of a non spectral interference
Matrix - something else bonds to the analyte so it is not detected
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)
A type of sample-taking technique that is fast but not necessarily representative
Name 3 ways to deal with matrix interferences
Add a releasing agent
Matrix match standards and blanks
Use standard addition
If get a false positive or false negative test result, what should you do?
Repeat the analysis
Name 3 types of blanks
Which two types of blanks are prepared in the field?
Which type of blank is prepared before going to the field?
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
From notes and Module 9 powerpoint