All major brands of soda syphon will fit these universal CO2 canisters.
Every party would be improved when you get out the soda syphon. They are now perhaps considered slightly kitsch which only adds to the charm. The process by which they work is that the CO2 is released into the soda syphon where some of it dissolves into the water, whilst inside the syphon then it is held under great pressure this cause more of the gas to dissolve into the water than would normally take place. When the trigger is pulled then the pressure of the gas above the water forces the carbonated drink out of the syphon. The drink will now be at atmospheric pressure not as much CO2 can dissolve in the water at this lower pressure so it starts to exit in the form of bubbles. The warmer it is the faster the bubbles will form and rise. The Pressure will also make a difference if you were to use a soda syphon on top of mount Everest then the whole effect would be magnified.
This video from Thats Life demonstrates how high the pressure of a soda syphon actually is.
The contents is pure CO2 and the chargers are held under high pressure.
These are disposable Carbon Dioxide chargers do not attempt to refill and recycle them.
Some CO2 information:
Carbon dioxide was one of the first gases to be identified as being distinct from the mixture that we refer to as air. The observations that indicated its existence were the fact the materials lost mass when burned even when no smoke was observed to escape. The change in mass was ascribed to an invisible substance which was later identified as Carbon Dioxide.
Fermentation is a natural process that creates carbon dioxide gas the reason drinks such as champagne are fizzy is because the fermentation takes place within a closed vessel (a corked bottle) so the CO2 is forced to remain in situ when the cork is popped the effect is very similar to pulling the trigger on you soda syphon.
50 CO2 Chargers
You will almost certainly have bought your CO2 chargers for the purpose of using to make fizzy water, that is after all exactly what they were designed for. You might also have an enquiring mind, so here is some information about how Carbon Dioxide behaves in the environment.
To begin with it is worth noting that we are carbon Based lifeforms, indeed it can be said that this is true of anything that has lived, is living and will live on this planet. Carbon dioxide is a gas and all around us (in relatively low concentrations) so how does this gas make our bodies?
Atmospheric CO2 is not the same concentration everywhere and if you were to get into a balloon and float upwards, you would find that the levels decreased as you got higher in the atmosphere (but not by much).
There are several routes by which the gas can be remove from the air, and several ways by which it can be released back into the atmosphere, this is referred to as the carbon cycle but in reality it can take millions of years for the cycle to be competed by some pathways.
Ways that CO2 can be taken from the atmosphere
The most obvious of these and the one you'll have been taught about at your primary school is photosynthesis. This is a process by all plants take in CO2 and use it to creating glucose. This is probably the starting point for life as we know it. Plants take in more CO2 the more they are growing, so a young tree will take in more than mature tree, and a fully grown woodland is almost carbon neutral it will take in the same amount of carbon dioxide as it releases. All plants absorb CO2 in daylight including the tiny photoplankton in the oceans.
Carbon dioxide is (slightly) soluble in water (this is why you're on this page looking at CO2 chargers in the first place) so the oceans are a sink for CO2 they absorb 30%-50% of all the carbon dioxide that is released into the atmosphere. The CO2 in the oceans can be either turned to carbonic acid that slightly acidifies the ocean, or hydrogen carbonates that neutralise acids. Sea creature that form shells will then turn the soluble hydrogen carbonate into insoluble carbonates (eg. Calcium carbonates) that they use to make their shells. Many types of coral also make a skeleton using dissolved hydrogen-carbonates. Much of the limestone rocks are formed from the exoskeletons of long deceased creatures, so are in effect the product of CO2 that was once dissolved in the sea, which illustrates that although was call it a carbon cycle, that does mean it is cycling quickly!
Ways that CO2 is put into the atmosphere
The all animals produce CO2 when they respire, that is how the energy from out food is actually turned into something useful. Plants also respire when they are utilizing the very glucose that they made from CO2 in the first place. The levels of CO2 present in a forest will change over days, nights, seasons as the plants go through processes of photosynthesis when the sun shines and respiration all the time. A human can breather out 1kg of carbon dioxide every day you've probably never thought of yourself as a contributor to global warming before have you?
Acids will react with carbonates and hydrogen carbonates to liberate CO2, this means that the more CO2 an ocean dissolves, the more CO2 is released by reactions of carbonates and the less hydrogen carbonates are available for sea creatures to make shells, or corals to make skeletons.
Rain which is naturally slightly acidic, will become more so as the levels of carbon dioxide in the atmosphere increase. The limestone (made from sea creatures) that has locked up masses of CO2 for millennia reacts with rain to release more CO2, which in turn will make the rain more acidic. This is part of the cycle, but it is now perhaps a cycle that is getting faster and running down a steep hill, slightly out of control as the breaks and pedals that once controlled are getting a bit to worn out!