Common Mistakes and Troubleshooting

A common error is over-interpreting a single positive colour reaction as definitive proof of a specific named compound rather than merely a chemical class;...

A common error is over-interpreting a single positive colour reaction as definitive proof of a specific named compound rather than merely a chemical class; corroborating chromatographic evidence should always be obtained before such a claim is made in a thesis or publication. Irreproducible TLC or HPTLC spot patterns between runs are most often attributable to inadequate chamber saturation or fluctuating laboratory temperature and humidity, both of which should be tightly controlled and documented. Where a mass spectrum yields an ambiguous molecular formula, acquiring the spectrum in both positive and negative ionisation mode, and cross-checking against the isotope pattern, will frequently resolve the ambiguity without requiring additional sample preparation.