I have a question about evaporation of organic solvents and the leftover sample after this is done. (sample dissolved in the organic solvent) Does the sample, leftover after the evaporation of a organic solvent, (used to dissolve the sample) affect the analysis of the dry sample? (basically, would there still be leftover organic solvent left, or does it all evaporate off? and thus not affect the sample analysis) This question applies to two situations I have: 1. I have to run a TLC plate and I was wondering if the organic solvent used to dissolve the compound mattered, since you evaporate it off before you run the plate. Does it affect the run? 2. Would there be a residual leftover of organic solvent on the sample after evaporation that would affect the spectrum of the compound when run on a KBr pellet in IR spectroscopy? Thank you.