Ethanol Lab Key

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Cocaine Correction Sheet – 20 points.
I. Objective (2 points)
A. The objective of the laboratory was to extract, identify, and quantify the
presence of cocaine on money. [1.5]
B. A secondary objective of the laboratory was to learn the technique of gaschromatography/mass spectrometry. [.5]
II. Procedure (4 points)
A. A dollar bill was sonicated for five minutes in a vial with HCl (8 mL) [.5]
B. The HCl solution was then basified with NaOH unitl pH >10 [.5]
C. The basic solution was extracted with CH2Cl2, dried with Na2SO4 [1]
D. The solution was then evaporated to dryness and 0.8 mL of CH2Cl2 containing
20 ug/mL? of benzophenone internal standard was added. [1]
E. The mass spectrum of this solution was then obtained. [.5]
III. Results (5 points)
A. Mass spectrum attached to your or your lab partner’s lab report [1]
B. Identification of cocaine peak [1]
C. Calculation of quantity of cocaine in your sample (or someone else’s if yours
didn’t have any) Cocaine, ug/mL = 83.83 * (area coke/area standard) -.2128 [1]
D. Class data table [2]
i. Label table, table 1, etc…
ii. Group number, ug/mL cocaine, denomination, year, ug (ug/mL * .8)
IV. Writeup (6 points)
A. Cocaine could/could not be identified. The library got a good match, peak
was clear, or otherwise. [1]
B. Only 1 group out of 11 (or class data only) – calculate % had cocaine on bill.
[1] Not enough info to see differences between denomination [1] Didn’t do
foreign currency [.5] – would be an improvement.
C. Quantitated on bill using calibration curve [.5] – what was range of values [.5]
D. Changes/improvements – could improve by using more, using foreign currency
[1.5]
V. Lab notebook (2 points)
Name/Partner [.25]
Title [.25]
Date [.25]
List of reagents/equip [.25]
Procedure [1]
Results
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