I always wondered about letting nitrogen flow into the flask like that, I thought that maybe it would be over pressurized and pop joints if you don't have a vent needle, but in this video I can see that once the flask and line is full of gas the rest just flows through the manifold and into the bubbler. I assume the flask is under a higher pressure than atmosphere, but is there any risk of blowing joints? We don't really use the Schlenk techniques in my lab but I want to know for when I eventually go to another lab (or need to use them in the future here).
thats what the bubbler is for. gas is always just flowing it cant overpressure because its an open system. the only pressure is from the oil which is easily overcome.
@@user-mp4bc9qp2x That makes sense. I am curious what is the purpose of using a ventilation needle when transferring liquids from a bottle with a septum if that's the case. I suppose the needle is small enough to where something might pop out and you don't want to take any chances when handling something like tBuLi.
@@user-ko7lz3kr1d i'm not sure what you mean. i dont use a vent needle when taking reagents from a bottle through the sure seal. it's just the nitrogen line with positive pressure. then you can remove solution via syringe. you use a vent needle when purging without vacuum so that the air can leave and be replaced with nitrogen
@@user-mp4bc9qp2x I've just seen quite a few demos online where someone will be handling a pyrophoric liquid and they'll use a vent needle for positive flow. We just use balloons in my lab anyways so I've never had any hands-on experience with Schlenk techniques.
what about the moisture that can be on the black pipes or in the rest of the system?
use the vacuum to suck it out - need a strong pump
I always wondered about letting nitrogen flow into the flask like that, I thought that maybe it would be over pressurized and pop joints if you don't have a vent needle, but in this video I can see that once the flask and line is full of gas the rest just flows through the manifold and into the bubbler. I assume the flask is under a higher pressure than atmosphere, but is there any risk of blowing joints? We don't really use the Schlenk techniques in my lab but I want to know for when I eventually go to another lab (or need to use them in the future here).
The glass , not withstanding cracks, won’t pose safety concerns.
thats what the bubbler is for. gas is always just flowing it cant overpressure because its an open system. the only pressure is from the oil which is easily overcome.
@@user-mp4bc9qp2x That makes sense. I am curious what is the purpose of using a ventilation needle when transferring liquids from a bottle with a septum if that's the case. I suppose the needle is small enough to where something might pop out and you don't want to take any chances when handling something like tBuLi.
@@user-ko7lz3kr1d i'm not sure what you mean. i dont use a vent needle when taking reagents from a bottle through the sure seal. it's just the nitrogen line with positive pressure. then you can remove solution via syringe. you use a vent needle when purging without vacuum so that the air can leave and be replaced with nitrogen
@@user-mp4bc9qp2x I've just seen quite a few demos online where someone will be handling a pyrophoric liquid and they'll use a vent needle for positive flow. We just use balloons in my lab anyways so I've never had any hands-on experience with Schlenk techniques.
thank you
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What is the purpose of the tee connection near to the oil bubbler?
three-way joint: air, nitrogen, oil