390 DIY Science: Illustrated Guide to Home Chemistry Experiments
SBSTITUTIU oNS ANd modIfICATIoNS- You may substitute test tubes for the spot plate, but
doing so increases the quantities of test reagents and
the sample sizes needed. - The Barnes bottles or dropping bottles are used to
store the reagents. You may substitute any small
bottle or stoppered test tube for storage and use Beral
pipettes or droppers to dispense the reagents. - You may substitute 0.17 g of ferric chloride
hexahydrate for the 0.10 g of anhydrous ferric
chloride. Ferric chloride solution is used as a circuit
board etchant, and is sold by some professional
electronics stores and suppliers.
CUTIOA nS
Perform this experiment only in a well-ventilated
area. Chloroform is toxic and carcinogenic. Methanol
is flammable. Sulfuric acid is corrosive and toxic.
Formaldehyde is toxic, corrosive, and a lachrymator.
Nitric acid is toxic, corrosive, a strong oxidizer, and reacts
vigorously with many organic and inorganic substances.
Ferric chloride is an oxidizer and corrosive. Wear splash
goggles, gloves, and protective clothing.z
and 40% formaldehyde. Samples are tested in powder form
and with chloroform as a solvent.Nitric acid reagent
Nitric acid reagent, which the NIJ designates A.6, is another
frequently used presumptive drug test. The nitric acid test is
very sensitive, particularly for mescaline hydrochloride, and
detects a wide range of illicit drugs, including amphetamines,
mescaline, and opioids like morphine and codeine. The nitric
acid test uses, as you might expect, concentrated nitric acid.
Samples are tested in powder form and with chloroform as a
solvent.
ferric chloride reagent
Ferric chloride reagent, which the NIJ designates A.8, is much
less frequently used than Marquis reagent and much less
sensitive. We’ll use ferric chloride reagent for this lab, because
it uses a readily available chemical that reacts interestingly with
many common household substances. Ferric chloride reagent
uses, as you might have guessed, ferric chloride. Samples are
tested in powder form and with methanol as a solvent.
Table 22-1 shows the color changes expected when the analyte
shown in the left column is treated with Marquis reagent,
concentrated nitric acid, or ferric chloride solution. An asterisk in
a color change column indicates that this is a preferred test for
this substance.
dR. mARy CHERvENAk CommENTS:
Ferric chloride is also used in wastewater treatment, but
good luck finding a local wastewater treatment store.TSTSE AmpLES
Obviously, I don’t recommend you attempt to buy samples of heroin, cocaine, methamphetamine, and other illegal drugs. No
matter how convincing you are, the judge is likely to take a dim view of your claims that you bought them only in the spirit of
scientific inquiry. Fortunately, there are alternatives that are just as good for the purposes of this experiment.
In addition to common household substances, you may be able to get legal samples of some controlled substances. For
example, some prescription cough medicines contain codeine, as does Tylenol with Codeine (Tylenol 1, 2, 3, or 4, in different
dosages). In some jurisdictions, some OTC drugs include codeine in very small amounts, which are nonetheless more than
sufficient for these tests. Also, if anyone in your household uses a prescription pain reliever, the smallest scraping from a tablet
or even the dust from an empty bottle is sufficient. If you have a pet, try testing tiny samples of any medication that your
veterinarian has prescribed.
You can also test samples of whatever prescription and OTC medications you have available. In particular, try testing pain
relievers (including aspirin and acetaminophen, naproxen sodium, ibuprofen, etc.) and allergy medications (including those
based on pseudoephedrine hydrochloride, chlorpheniramine maleate, brompheniramine maleate, and so on). The kitchen spice
rack is also a fertile source of herbs, spices, and other possible test samples (poppy seeds!), as is the garden shed, with its
selection of insecticides, fertilizers, and so on. Use your imagination, and test as many substances as you have time for.