posted by Lucas Hockenbury on .
is the fizz from soda pop a chemical reaction?
No. Carbon dioxide (CO2) gas is dissolved in the soda (under pressure). When the cap is popped, the pressure is released and the CO2 comes out of solution. In most cases, solubility is a physical property but that is not always true. However, on a smaller scale, there is a very SMALL amount of H2CO3 in the soda and it is in equilibrium with
H2CO3 <==> H2O + CO2.
That part of the reaction is chemical but the fizz itself is just from the release of the pressure.