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Potassium carbonate and hydrochloric acid in sealed bottle?

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sprotz:
What happens when hydrochloric acid is added to potassium carbonate in a sealed bottle? Does the reaction give off co2 that builds up pressure, and does the reaction stop at a certain pressure or does the reaction continue until all the co2 is released?

chenbeier:
It will continue until all CO2 is released. Pressure rises.  You get a sparkling salty water or the bottle explode before.

AWK:
It all depends on the molar ratio of HCl:K2CO3 and the order of the addition of reagents.
If HCl is less than 1 mol to 1 mol of K2CO3 then at good mixing no CO2 will evolve.
K2CO3 + HCl = KHCO3 + KCl.
At a molar ratio of HCl>1 to 2, potassium carbonate will decompose with the evolution of CO2.
KHCO3 + HCl = KCl + H2O + CO2
This explanation applies to the addition of acid to carbonate.

In the reverse order of the addition of the reagent, potassium carbonate will decompose with the evolution of carbon dioxide until the molar ratio of HCl:K2CO3 will reach 2:1 or until the acid runs out.
K2CO3 + 2HCl = 2KCl + H2O + CO2
With excess potassium carbonate in a sealed vessel, the following reaction will occur:
CO2 + K2CO3 + H2O = 2KHCO3

Even such a simple reaction can be so complicated.

sprotz:
Thanks for the information. Because I learned that rate of co2 emission decreases with increase in pressure and eventually stops in case of a carbonate with acetic acid. Maybe with a stronger acid the threshold is higher? So if co2 continues to form and pressure rises, would this be an easy way to collect and store co2 in a pressurized tank, maybe liquid co2 will form if pressure gets high enough?

Enthalpy:
Liquid CO2 can exist up to 31°C, but it needs 74bar there, which most "bottles" don't resist.

Easier ways exist to obtain liquid CO2, in case it's useful.

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