How to tell when it's time to call it quits, for example when production slows to a drop every X number of seconds? I just want to make sure I'm
getting the most out of my reagents.Pyro - 4-9-2013 at 08:22
just keep heating until the temperature read on the thermometer goes over the BP of HNO3, also the production of NO2 will cease.Pulverulescent - 14-9-2013 at 04:49
Quote:
. . . just keep heating until the temperature read on the thermometer goes over the BP of HNO3, also the production of NO2 will cease.
HNO3 boils @~83°C but distills from H2SO4 @ between 90 and 121°C!
When finished, the temp. will start to rise fairly quickly and heating may then be stopped . . .
eidolonicaurum - 9-1-2014 at 08:24
I wait until a drop every 5 seconds or so. Chances are, when the distillate is not coming over very quickly anymore, anything left in the flask is
removing, unless its very precious. Ie. I just get bored, and stop when its about done as above.Metacelsus - 9-1-2014 at 18:33
On distillations such as this, I wait until the temperature in the still head peaks and then starts to decrease. This usually signifies the end of
vapor production. Patience is key. However, this only works with fractions far in boiling point (e.g. nitric and sulfuric acids).
