test 3 AA Multiple Choice Identify the choice that best completes the statement or answers the question. ____ 1. For an ANOVA comparing three treatment conditions, what is….
What was the total correction factor between the count rate and the activity of the system used to count 131I mounted on Mylar?
9-6. A 131I standard solution was obtained from the National Bureau
of Standards (NBS). The following information was supplied concerning
the solution: assay of 131I at 8 A.M., January 1, 2.09 ×
104 dps/mL } 2%. On January 15 at 8 A.M., a sample of 131I was
counted. This sample had been obtained from a shipment of 131I
in the following manner: 20 λ (I λ = 1μL) of the shipment was
diluted in a volumetric flask to 25 mL; 100 λ of this solution
was diluted to 10 mL; and 50 λ of this solution was withdrawn,
mounted on Mylar, dried, and counted. The dried sample provided
a count rate of 4280 cpm corrected for background. At the same
time (8 A.M., January 15), a 50-λ sample of the NBS standard 131I
solution was mounted, dried, and counted in the same manner.
The count rate for the standard sample was 1213 cpm corrected
a. What was the specific activity (millicuries per milliliter) of the
131I shipment at the time the sample from the shipment was
b. What was the total correction factor between the count rate and
the activity of the system used to count 131I mounted on Mylar?