I tried this experiment lately and this happened, I shook a coke bottle and its air pressure remained the same but the coke came squirting out when I opened the lid. How is this possible?
Why does the air pressure not increase when I shake a coke bottle
chemical compoundshome-experimentliquid-statepressurethermodynamics
Best Answer
Shaking the container distributes small bubbles through the liquid. These act as nucleation points at which the dissolved CO2 can boil out of the solution, much like how water in a steel pan will start to boil at places where the pan is scratched. If the pressure in the container is lower than the vapor pressure of the CO2 still in solution, pressure will increase up to the vapor pressure rapidly as CO2 boils out quickly at the distributed nucleation points, rather than continuing its slow process of evaporating out through the surface. If, however, the pressure in the container is already higher than the vapor pressure, pressure will not increase much. In either case, the pressure inside the container only affects the degree to which the soda will froth up insofar as it increases the maximum amount of CO2 that can be dissolved in the solution. The concentration of CO2 in solution and the availability of nucleation points are the primary factors in "fizziness".