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Each group of students should work together to think about their problem. This assignment is meant to take between 30 and 60 minutes. One group solution should be proposed to the problem. The purpose of this problem is to review the principles of sampling and also the role of sampling in the total analytical process. If additional information is needed, you may consult Dr. Sherren as a group or any resources in the Library. Each group member is responsible for the understanding of the problem and the proposed solution to the problem. Be sure that all members of the group understand the problem. All group members should sign the final group solution that is submitted. The overtime problem should proceed much more rapidly after completing the first problem.

All groups are employees of the NCC Analytical Company. Each group has a related problem, but the incoming material to be sampled for analysis is different.

A Semi-Truck pulls up to the loading dock. The truck is filled with (see the list below). Your instructions are to obtain a representative sample from the truck for the analysis of Arsenic. You must run six samples. These samples are to be representative of the entire truck. Using the details for the Arsenic SOP tell how your group will work together to obtain a representative sample. You have good equipment and may assume that you have any of the tools for sampling listed in the text. You also have a clean room to use if needed for inside preliminary work. Remember that good protocol calls for being able to rerun the analysis and also to have about half of the sample left after you write your report of the analysis. For the overtime portion of the problem, the truck is a large truck that would carry liquids. PROBLEM FOR GROUP 01
The truck is filled with Illinois SoyBeans.
For overtime the boss asks you group to sample a truck filled with Wisconsin milk.

The truck is filled with Georgia Watermelons.
For overtime you boss asks you to sample a truck filled with Illinois Corn Syrup.

The truck is filled with Western Hard Coal.
For overtime your boss asks you to sample a truck filled with Pineapple juice.

The truck is filled with Soil from the West Chicago Rare Earth Plant.
For overtime your boss asks you to sample a truck filled with packing plant wastes.

SOP for the Determination of Arsenic for the NCC Analytical Company.
All analysis are to be run on an "as received basis". Then the analyst must do a moisture determination to calculate the presence of the analyte on a "dry weight basis". For the current regulations six replicates must be run of each substance being run. The analyst follows the procedure found in the NCC CHM 210 Laboratory Directions for the Determination of Arsenic by Titration with Iodine Solution.



Group 01 Group 02 Group 03 Group 04