Additional Related Projects

• Alternative dichloramine preparations. (Note: The resulting solutions can be analyzed by UV spectrometry as described in the experiment above).

1. React hypochlorite with ammonia (in 10% excess) in a dilute basic medium at 0°C to prepare the monochloramine. Then, add slowly dilute perchloric acid to the resulting solution (to a pH of 3.5—4) to prepare the dichloramine. An excess of acid will produce the trichloramine.

2. Prepare the monochloramine and then make the resulting solution trickle down a cation-exchange resin bed. As it turns out, there exists a quite acidic medium in the interior of the resin grains and, as a result, the NH2CI undergoes dismutation to yield NHC12 + NHj.

• Trichloramine concentration. Produce the trichloramine as described in the present experiment and then extract it with an organic solvent (for example, try baby oil) so as to obtain a more concentrated solution. Run a UV-VIS scan as above and compare it to that obtained with the non-extracted solution prepared earlier (see Pepi, 2003).

• Once the absorbance spectra are taken for each chloramine solution in the present experiment, change the pH of each solution and predict and verify the new major absorbance peaks.

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