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zoas23
02-02-2016, 10:16 PM
Which ones are all the methods to seal a glass flask?

i.e, those who followed the "Nav's path"... how did you seal your flasks? (the idea there was to prevent an escape from Ozone or Hydrogen or some sort of gas that nobody defined clearly and some people even assumed that such gas was simply not there).

But the quesion also goes for other types of flasks and other types of experiments:

i.e, if you have a Kitasato and you are not using a vacuum pump and you need to seal the arm that normally gets connected to the vacuum pump, which substance would you use to seal that arm?

JDP
02-03-2016, 11:25 AM
Which ones are all the methods to seal a glass flask?

i.e, those who followed the "Nav's path"... how did you seal your flasks? (the idea there was to prevent an escape from Ozone or Hydrogen or some sort of gas that nobody defined clearly and some people even assumed that such gas was simply not there).

But the quesion also goes for other types of flasks and other types of experiments:

i.e, if you have a Kitasato and you are not using a vacuum pump and you need to seal the arm that normally gets connected to the vacuum pump, which substance would you use to seal that arm?

There is always an inherent danger in sealing flasks that are going to be heated. In the past we hear of seekers after the Stone complaining about explosions in their labs, and it was usually because of this. Some of those totally phony "recipes" that we see circulated widely among "puffers" are in fact a prescription for an accident waiting to happen. For example, we see some of these totally phony processes instructing to dissolve a metal, say silver, in "aqua fortis" (nitric acid) in a sealed flask. This will undoubtedly result in a violent shattering of the flask, since the nitrogen oxides that are generated during the solution of the metal will NOT go back into a liquid or solid state and will keep on accumulating pressure inside the flask until the glass walls can no longer hold them and will burst to pieces. There is in fact a valuable lesson to be learnt from such examples: the alchemical solvent has the peculiarity of coagulating into a solid substance, given due digestion with its proper "earth" or "body", something which most common solvents of ordinary chemistry simply will not do. That simple fact by itself allows the astute seeker to discard a large amount of common solvents that will not do such a thing. This feature of the alchemical "Water" to coagulate itself with controlled heat + the right "earth" or "body" is in fact so unusual that an Arabic alchemical poem attributed to Khalid Ibn Yazid mentions it as a sure sign of being on the right track:

"When I saw the Water coagulating itself I became sure that the thing was right as has been described." - quoted by Ibn Umail in his Book of the Silvery Water and the Starry Earth.

As for how to seal flasks: you can use a rubber or ground-glass stopper with clamps, hooks or weights on them to hold them in place. Or you can do it like the old-timers did: use a strong "lute" to keep the stopper in place, or fuse the upper part of the walls of the neck of the glass flask together, as shown in the flask illustrated in Salomon Trismosin's Splendor Solis during the "coction" of the Stone. Example:

http://www.hermetics.org/solis/images/solis13.JPG

But be very careful, a heated sealed flask can always shatter due to internal pressures, even if you have stumbled upon the correct "Water" of alchemy. I recommend to construct a "shield" from a couple of thick sheets of lexan (a transparent and very strong plastic sold in most hardware stores), to be placed in between the observer and the heated sealed glass flask. If it bursts to pieces, the lexan sheets will stand between you and the flying pieces of glass and hot contents of the flask. Follow my advice and you will thank me later for having saved you from potential injuries to your face, chest and arms.

zoas23
02-03-2016, 02:26 PM
Thank you, JDP!!!!! As always, incredibly useful.

My question is mostly related to Kitasato flasks and how to seal their arm.
(Short story: the FIRST equipment I had was the equipment of a former alchemist whose wife got mad at him because he set a part of his house on fire... so he sold his used equipment on a local version of eBay as a "combo".... I bought it because he charged for some 50 pieces of glassware the same thing that I pay for only 1 piece... the "combo" included 6 or 7 Kitasatos and I want to seal their arms in a non permanent way, rather than making them 100% hermetic).

Other than that, it's a privilege to be able to talk to you and receive your advice.
I can't stop repeating the same sentence again and again: "I fucking love this forum!".

JDP
02-03-2016, 02:39 PM
Thank you, JDP!!!!! As always, incredibly useful.

My question is mostly related to Kitasato flasks and how to seal their arm.
(Short story: the FIRST equipment I had was the equipment of a former alchemist whose wife got mad at him because he set a part of his house on fire... so he sold his used equipment on a local version of eBay as a "combo".... I bought it because he charged for some 50 pieces of glassware the same thing that I pay for only 1 piece... the "combo" included 6 or 7 Kitasatos and I want to seal their arms in a non permanent way, rather than making them 100% hermetic).

Other than that, it's a privilege to be able to talk to you and receive your advice.
I can't stop repeating the same sentence again and again: "I fucking love this forum!".

The thing is that Kitasato flasks are not made for that purpose, but for vacuum filtering:

https://www.dartmouth.edu/~chemlab/techniques/vfiltration.html

You are not supposed to make a permanent vacuum in them or heat them. Their flat bottom conical shape is not the most ideal to resist internal pressures. Round or cylindrical flasks would be better for this purpose:

https://www.chemglass.com/product_view.asp?pnr=CG-1880

https://www.chemglass.com/product_view.asp?pnr=CG-1880-R

Notice the healthy advice of the manufacturer:

IMPORTANT NOTICE: ALL CHEMGLASS PRESSURE VESSELS ARE TESTED AT 150 PSI, OR APPROX TWO AND ONE-HALF TIMES THEIR RECOMMENDED WORKING PRESSURE. HOWEVER, CHEMGLASS DOES NOT GUARANTEE THE VESSEL FROM BREAKING UNDER PRESSURE, DUE TO THE NATURE OF MATERIAL AND CONDITIONS BEYOND OUR CONTROL. CHEMGLASS RECOMMENDS THE USE OF SAFETY SHIELDS AND/OR OTHER SAFETY EQUIPMENT.

Even for vessels specifically designed to withstand internal pressures it is recommended to put a shield between the operator and the vessel.

zoas23
02-03-2016, 03:00 PM
Thank you, JDP again!

I do not use a shield (though I always use gloves, protective lenses and a mask that covers the mouth and the nose... even when I'm doing things which are 100% safe).

I will adopt the shield too... I am always very cautious with safety.

Some time ago I found the Philosopher's Stone (it came in the shape of a girl and I asked her to be my girlfriend, I've been lucky and she said: "yes"). ;) <<<---- this is 50% a joke and 50% something true.

She made me promise that I will always be cautious and do everything in a safe way when it comes to the lab... and I keep my promises. Thank you for your advice about the shield, I will definitely adopt it.

Thank you for the advice about the Kitasato flasks too.