Lab Tips: Back flow prevention when dissolving highly soluble gases

In this video I will show you a simple way to prevent back flow or "suck back" from happening using simple lab items.

Category:

Science & Technology

Tags:

• lab tips
• back flow
• suck back
• back flow prevention
• dissolving gases
• HCL
• ammonia
• HBR
• ammonia gas

[lexichronicle2]

This method is actually better in terms of back flow, because it prevents it rather than just catching it in another container.

You're videos are great, they're about the only ones related to home chemistry that I bother watching any more.

[ytmachx]

Great camera work, excellent explanation and demonstration!

[shiftgood1]

WELL THAT YOU AGAIN. No more miseries with the dreaded back up. This works for making formaldehyde, and many other applications.

(I speak in addition to my preaching slow stickers on vehicles, part time work only, THE BOX, publishing on waist receptacles, saying this as a "greeting" in all stores and seeking Higher Power first. for 12 years and more). Again

Great Stuff. No more hazels with that dreaded back flow.

[mcwario13]

me and my colleague are wondering how to make hcl and we were wondering if aluminum chloride or aluminum trichloride would decompose to produce chlorine when we make HCL?

[mrhomescientist]

This is an excellent way to prevent suck back, I've used it a few times to great effect! How did you generate your ammonia gas? What was the concentration of your finished solution? I tried making conc. ammonia using the same basic setup as yours, plus heating the reaction flask to drive out the NH3 into the collection beaker, but I can't get my final solution to be very strong at all. Any tips?

[AlChemicalLife]

:) good tip. even though i have no head phones i got the point when i saw the ap with the funnle. good job :) i will have to use this when im makeing hcl and other good thing like that.

[jr14103]

Great tip!!! It's nice to find a good home chemist!!!!

[TerminalRhinoVirus]

Very clever man.

[yellowmetalcyborg]

Nice tip! To minimise losses, what I do is I bubble the required gas directly into my reaction mixture where it is needed. The gas is used up as soon as it is dissolved so that losses are minimal.

[endimion17]

@homealchemy You can push it to 30% or a bit higher (laboratory ammonia is a bit over 25%) if you use ice cold water. Remember that it gives off ammonia like crazy while it warms back to room temperature.

So just transfer the ice cold saturated solution in a glass bottle with a gasket screw cap and keep it at a cold place. Obviously, if you try to open it while it's warm, it will produce a hissing sound (might even bubble up) immersing you in a cloud of ammonia, so be very careful.

[endimion17]

Yeah,this has always been a neat way to dissolve ammonia and hydrogen chloride.The only thing one has to be very careful about is the position of the funnel.It depends on the funnel,but it's usually enough to place its rim exactly on the surface of the water.Immersing is rarely required,especially with HCl and NH3. As you know, those gasses dissolve so rapidly in cold water that bubbles don't even form.There's usually a dynamic equilibrium,so the phase boundary remains motionless.

Cool video. :)