Page 11 - Prescription for Crime Drug Testing
P. 11
Lab 2, Part B Solutions
❖ What four concentrations of drugs were used ❖ Concentration of the unknown solution
in this analysis? (meth):
0.25 mg/ml, 0.50 mg/ml, 0.75 mg/ml, Concentration = (peak height 0.5)/88.8
1.00 mg/ml concentration = (75.5 0.5)/88.8 concentration
= 0.844 mg/ml
❖ What does 1.0 mg/ml signify?
There is a concentration of 1.0 mg of ❖ Determining the concentration: Sample
methamphetamine for every 1 milliliter of concentration: 0.844 mg/ml
solvent the chemical is dissolved in Original sample concentration: 2 mg/ml percent
concentration: 0.844/2 = 42.2%
❖ Scatter plot trendline equation (may vary
slightly): ❖ Calculating the quantity of meth in the
y = 88.8x 0.5 sample collected by police:
qty = concentration * mass qty = 0.422 * 13g
qty = 5.48g
❖ Scatter plot trendline equation solved for x,
where x is the concentration of the substance
being tested and y is its peak height on the
GC graph:
x = (y-0.5)/88.8
THE MYSTERY OF LYLE AND LOUISE 11
