C02 Vinegar/Baking Soda math question

Bryan

Active member
Hello:

Ok a bit of topic, but wanted to generate some CO2 and stumbled upon this that is apparently the correct ratio of household vinegar and baking soda to efficiently generate a given amount of C02.

But I have access to cleaning vinegar which is 10% acetic acid vs 5%.

SO, does this mean I can half the amount of vinegar for the given amount of baking soda. I can just use 100ml of vinegar and 13.9 grams of Baking soda?


The reaction is as follows:

NaHCO3 (aq) + CH3COOH (aq) ......> CO2 (g) + H2O (l) + CH3COONa (aq)

Thus: 84gmw 60gmw 22.4L gas (i mole)

THE APROX CALCULATIONS ARE:

Because Vinegar is only 5% acetic acid - 200ml of vinegar has about 10 grams of acid or 16.6% of a mole of acetic acid.

We need 16.6% of a mole of baking soda which is 13.9 grams.

Thus you would get 16.6 % of a mole of gas or 3.7 Liters of CO2 gas which equals about .97 gallons of gas
 
Thanks kindly much appreciated. I suppose if one can source some pure acetic acid you would adjust the volume proportionally, but I suppose at some point you are dealing with a slurry as opposed to a solution.

If I can pick your brain on one more point. Using the calculator below and if it is correct then as a ballpark I can expect around 7 p.s.i. if the solution was mixed in a 1 litre container.

0.85 L (approx. volume left after solution in a 1 litre container)
16.6% mole of gas
78 degrees Fahrenheit

https://www.gigacalculator.com/calculators/ideal-gas-law-calculator.php
 
The reaction creates C02, according to the instructions 200ml of vinegar and 15 grams of baking soda should create 1 gallon of C02?. I wanted to know the psi if it was compressed into a determined space, the calculator suggest approx. 7 p.s.i with the parameters I provided, or at least I think it should.
 
Ah, I see, you mean to seal the container to capture the gas. I was confused for a minute. Let me work through the math.
 
Yes thanks, I am pretty sure the calculator has it right, just not sure. Have a old fire extinguisher that can be unscrewed and refilled (powder type) and wanted to experiment with creating a co2 source, just didn't want to get too crazy with the pressure.
 
Hmm, that seems high, here are the values I used. The container is 1 litre, but I took away 150ml to compensate for the solution.

Annotation 2020-07-17 141432.png
 
Ooops, changed to .16 and yes 75 p.s.i, Gee that is surprising how much pressure.

So for example if I tripled the "recipe" and created more co2 would the 0.16 would become .48 and the volume of the container becomes .4 litre for a psi calculation of 432 p.s.i or shouldn't the percentage of co2 still be at .16 but the volume of the container is smaller for a value of 144 p.s.i ?
 
Yep, that's what I got.

Remember that the container will start at 15 psi because it'll have air in it (I presume). This process could be rather dangerous. Is there some reason to capture carbon dioxide?
 
Actually looking at a quick and easy option to provide some co2 for a nano FW planted tank. I have the co2 hardware to do so, but need to have the bottle hydro tested.

Thinking I could do something much smaller, am actually think now using the yeast/sugar method and let it free run. Can control it with a 3 way miniature clippard valve that I have. The 3rd port just vents to the atmosphere.

In a sense just playing around and bantering some ides about, was curious as to the pressure that one could store from a vinegar/baking soda solution.

Thanks for all your help.
 
You're welcome. If you want to continue along this line, you might be better off capturing the carbon dioxide with a plastic bag or balloon of some sort that would break before building up much pressure.
 
More of a temp solution until I get the older co2 hardware in operating condition and upgrade the tank. Need a new needle valve, tank needs to be hydro tested. I am comfortable just using a soda bottle or the fire extinguisher as a vessel. Going to go with the sugar/yeast method and run it without back pressure. 3 way valve will turn off any Co2 to the tank when not needed and just vent to the atmosphere so no backpressure, other than just the air stone.

Glad I checked and posted about the pressure, original plan was to supercharge the fire extinguisher with a vinegar/baking soda solution, but I had to tap the needle valve into the plastic nozzle of the extinguisher. I am sure the pressure well over 100 psi would have blown it out.
 
Back
Top