Are you sure it was CaCl2, not CoCl2? But the color have changed, so the thiocyanate complex is not dominating in the solution. I guess my second question is a more general one. With the twenties, one set of 4 bills was strongly positive, the other was inconclusive. A diffeent reaction from the Sodium hydroxide here. Strangely, the mixture didn't seem to be a solution when placed against light. Nevertheless, I could see shifts to blue color several but not all trials. You don't want it so wet that the bill becomes noticeably wet.
Thank you for referencing the forensic book and the link, it was a new resource to me. However, i don't understand how you determined that it will only dilute the solution and not truly effect the equilibrium. Conclusion: Change in color from blue to pink indicates the creation of cobalt aquo complex. The amount of cocaine on any single bill varies widely based on location, age, and other factors. When the solution, together with crystals is poured into a glass with distilled water, the crystals turn pink due to formation of cobalt aquo complex.
. Keep work area neat and clean and have chairs or any wires out of walk way, precaution of tripping over them. Wear splash-proof goggles, apron, gloves and closed toe shoes. Only few ppt was left over. If i have a mixture of 0.
After concentrating material on the Q-tip, I added 2 — 3 drops of 0. Stability constants for iron thiocyanate complexes are much larger then for iron chloride complexes - log of first constant for FeL 2- complex, where L stands for ligand is 3. I look forward to hearing about your future explorations! You don't want it so wet that the bill becomes noticeably wet. I found better results using water for benadryl extraction would sometimes get negative results using methanol. This will favor the transfer of material from the Q-tip to the bill. How To Calculate Limiting Reagents Coming Soon! A moist tip favors transfer from the bill to the tip.
Examples: Fe, Au, Co, Br, C, O, N, F. Turns out this challenge was a bit tougher than I initially imagined it might be! Please tell about this free chemistry software to your friends! The solutions used in this lab has to be handled with care, since some of these chemicals can cause skin burns and eye damage. Reaction stoichiometry Limiting reagent Compound Coefficient Molar Mass Moles Weight 1 129. In a total of 19 trials, 7 resulted in a positive test, 11 were negative, and one test was deemed to be inconclusive an extremely faint color change to blue was observed. Addition of the cobalt thiocyanate reagent to cocaine hydrochloride results in the surface of the particles turning a bright blue faint blue for cocaine base. On adding xs Cyanide salt, the brown colour remained but when filtered, the solution obtained was the same brown colour.
These compounds are known false positives for cocaine. Let me know if you think this is the case. It worked great, even with just one pill crushed in the mortar. If you are not getting a positive test using the benadryl, then I would suspect you could improve your extraction technique. Thus, wet tip and dry bill as much as you are able.
However, i don't understand how you determined that it will only dilute the solution and not truly effect the equilibrium. Thus, I did not try this recipe. Or is the change in color from purple to pink simply a matter of dilution water causes the solution to dilute, thus making the purple color faint and hence pink? However, i don't understand how you determined that it will only dilute the solution and not truly effect the equilibrium. I then brought in a benadryll pill the next day, crushed it, and coated a bill in it, but then still got a negative test. You can see this procedure carried out in the video below: You will note that the positive results achieved were subtle. That is, is adding water also adding stress to a system? Or is the change in color from purple to pink simply a matter of dilution water causes the solution to dilute, thus making the purple color faint and hence pink? If i originally had CaCl2.
Best, Borek -- Chemical calculators for labs and education Yes, i meant CoCl2. This was done to so as to concentrate material on to the same area of the Q-tip to increase the probability of a positive test. Also, if there is in fact a stress, what is the direction of the equilibrium shift? If the procedure is adjusted to basify the sample rather than acidifying it, the test can be used to test for ketamine hydrochloride. Add Fe No3 3 c. Thank you for referencing the forensic book and the link, it was a new resource to me. That is, is adding water also adding stress to a system? The Q-tip should be moist, but not dry. I don't seem to understand how to investigate the effects of the reagents on the equilibrium reaction.
The following compounds were mixed with the Cobalt salt of which 15 produced a valuable result. If desired, the mixture was heated gently to increase rate of reaction or added in exess to detect further complex reactions, usually the dissolving of the ppt just formed. Conclusion: Change in color from blue to pink indicates the creation of cobalt aquo complex. It sounds like you got very good results - much better than I. I don't seem to understand how to investigate the effects of the reagents on the equilibrium reaction. Examples: Fe, Au, Co, Br, C, O, N, F. However, I got a positive result when I dripped a drop of the test solution into the mortar I used to crush the pill so it must be my swabbing technique that is off or I was too impatient waiting for a color change on the swab.
See the for information about the specific content types. I managed to get some bills in a big city near me and so I'm going to play with it some more this coming week and will try to post another reply if I get success. But the color have changed, so the thiocyanate complex is not dominating in the solution. Chemical calculators for labs and education. If you don't see precipitate, but you see some color change there is only one explanation - thiocyanate are complexing strong enough to not allow precipitation yet.