Reactions as a Test for Solvents

Hermannus Boerhaave (1668-1738) De menstruis dictis in chemia, in Elementa Chemiae (1733f 

Well then, my dear listeners, let us proceed with fervor to another problem Having sufficiently analysed in this manner the four resources of science and nature, which we are about to leave (i.e. fire, water, air, and earth) we must consider a fifth element which can almost be considered the most essential part of chemistry itself, which chemists boastfully, no doubt with reason, prefer above all others, and because of which they triumphantly celebrate, and to which they attribute above all others the marvellous effects of their science. And this they call the solvent (menstruum). 

Halogenated solvents and KCN are highly toxic. These experiments should only be carried out in a well-ventilated hood and not by schoolchildren and students  

Ten large test tubes with stand, hard white cardboard, glass rods, two 1-L beakers, gas burner, exsiccator, safety glasses, protective gloves. 

Sulfuric acid, formic acid, acetic acid, ethanol, methanol, trichloromethane, dichloromethane, dimethyl formamide (DMF), dimethylsulfoxide (DMSO), dicyanobis(l,10-phenanthroline)-Fe(lI), 30% H2O2, solid NaOH. 

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