Driving home from work, I was drinking a soda. It being a hot day, and me not having A/C in the car, the can got slippery with condensation. Naturally, I dropped the can, into my footwell. I quickly picked it up, but about half the soda in the can had spilled out. My next swig, the soda was flat, which, I suddenly realized, is always what happens when you drop and spill a can of soda.
Why?
I would expect the carbonation to be evenly distributed through the liquid – it certainly isn’t the case that, drinking normally, only the first half of the can is carbonated. Is it the dropping, or the spilling, or the dropping and spilling that causes the carbonation to disappear?
BTW – I’m a humanties type – a non-jargony explanation would be much appreciated. Thanks!
The coarbon dioxide is suspended in the fluid and held there by presurization in the container and the temperature of the fluids. Carbon dioxide is lighter then the fluid and lighter then the atmosphere outside the open container and it’s natural propensity is to raise. The combination of the warm weather - raising the temperature of the fluid and jolting accelerates the Co2’s natural inclination to find equilibrium - escape the fluid that contains it. I think. 
The jolt from dropping the can suprised the CO2 and scared it away. So it all flew out like a startled flock of crows rather than leaving a couple birds at a time to fly off and roost. Either way, eventually all the birds would have left the field, but when you dropped the can, they all left at once.
