Titi - 16-11-2025 at 11:17
Hi everyone,
I have been for a long time searching for an effective way to store gas, not under pressure, for use for experiments. The easiest way is to just
reverse a beaker in another, and collect the gas under water. Obviously, this makes it difficult to use the gas for later.
A nice way is to use two gas burette, connected from below, one higher than the other, filled with water (or mineral oil for reactive gases). This
allows to store, reuse, and measure the gas consumption of a reaction. Using an inverted dropping funnel in a beaker is similarly convenient.
However, both of them are very limited in volume. It seems that there existed apparatus for storing larger volume of gas under water, as
https://commons.wikimedia.org/wiki/File:Berzelius_gasometer....
but does not exist anymore. Is it possible to make such an apparatus or similar from available glassware, maybe up to small modifications? 5 to 10L of
gas would already be much more convenient.
What are other possibilities for storing gases, without pressure, in a reliable way and measurable way? (for a few hours/days)
Radiums Lab - 17-11-2025 at 11:06
For few hours U could cool it using LN2.
Twospoons - 17-11-2025 at 12:27
Balloons no good for you? I'm thinking the metallized plastic helium balloons.
Or you could use 2 glass 4.5l demijons, as used in wine making, with 2-hole bungs and linked with suitable tubing. The fluid link tube would need to
extend to the bottom of both demijons. Changing the height of the overflow demijon would let you adjust the gas pressure too.
[Edited on 17-11-2025 by Twospoons]
Radiums Lab - 17-11-2025 at 13:17
Sorry didn't think of balloons. But you will have some losses due to diffusion.
Twospoons - 17-11-2025 at 14:36
Thats why I would go with helium rated balloons. Anything that can hold helium for a couple of days has to be pretty impervious to anything else.
Sulaiman - 17-11-2025 at 19:28
iI think that rather than generating and storing gasses,
it would be better to have a controllable gas generator.
either a Kipps apparatus type https://en.wikipedia.org/wiki/Kipp's_apparatus
for sale are lovely glass units, or more affordable plastic ones.
or a flask and addition funnel.
most gasses can either be diy on demand,
or purchased in a bottle (eg argon)
What am I missing ?
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a diy gasometer should be simple, https://en.wikipedia.org/wiki/Gas_holder
an upside down bucket in a tub or bin of water,
a bit of mechanical stabilisation, a couple of tubes, some sticky stuff,
and maybe a weight on the bucket to increase pressure/reduce volume.