The reason why it's not done in organic chemistry is pretty much self-evident: look at some of the chemicals you yourself mentioned... volatile &
flammable + open flame = recipe for an accident!
But in inorganic chemistry it can be done, as long as no flammable materials are being dealt with (preparation of nitric acid from a mixture of sodium
nitrate and sulfuric acid, for example.) Borosilicate glassware, specially the round bottomed pieces, can take the thermal shock very well (at first
the flame should be yellow, though, not an air/gas mix blue flame at the full blast of the burner! Even the best round borosilicate glass pieces can
crack with such a brutally sudden thermal shock.) |