When preparing a copper etching plate for etching, it must be degreased completely before putting on the etching ground. Otherwise the acid may "bite" through the ground ("foul biting") in spots not desired. Whiting has been used for degreasing and alcohol has also been used successfully. I was w...

Our teacher had taught us that cis-trans-[10]annulene is non-aromatic. The reason he gave is due to repulsions between hydrogens, the structure is no longer planar But later he told us that [14]annulene is aromatic. But isn't there a repulsion between hydrogens in [14]annulene too. In fact, the...

Some even very significant discoveries have been accidental, but if science is supposed to be rational, then accidents should be oddities for this if they cannot be quantified. Are there generally accepted (or official-like) guidelines about what the role of "accidents" are or can be in professio...