Reflux apparatus understanding

  • Thread starter Rajini
  • Start date
  • #1
621
4
Hello All,
I have a doubt in reflux apparatus. Usually when we heat some solvents in a glass flask it may evaporate..and this vapour is cooled by reflux condensor and again go into boiling solvent. So on heating the amount of solvent won't decrease or decompose. What I want to know is whether the flask is closed or left open to atmosphere while heating?
Regards, Rajini.
 
  • #2
the flask is closed or left open to atmosphere while heating?
Ordinarily, NOT ALWAYS.
 
  • #3
It is very seldom a good idea to heat a completely sealed apparatus, as pressure can build up and cause it to explode. If your reactants are water sensitive, a drying tube can be placed on top of the condenser to eliminate moisture, and if they are oxygen sensitive the apparatus would need to have a stream of inert gas supplied, or be run inside a glove box.
 
  • #4
Hello Bystander,ManiacaLaugh,
Thanks for your reply. My reactants are oxygen sensitive. Also I cannot heat inside a glovebox/bag! So plan to pass continuously an inert gas (Ar) while heating (30 to 60 min of heating around 250 celsius is enough for my case).
Regards, Rajini.
 
  • #5
So plan to pass continuously an inert gas

Depending on how sensitive your reactants are, you may want to use an oxygen scrubber with vanadium(II) chloride solution.
 

Suggested for: Reflux apparatus understanding

Back
Top