After the bottle is sealed, the CO 2 is trapped in the liquid, but would rather leave the solution. Therefore an equilibrium is established between the amount of CO2 in the liquid and the pressure of CO 2 gas in the top of the bottle.
When you open the bottle, there is a dramatic decrease in pressure over the liquid, so the CO 2 starts to leave the liquid very rapidly, causing the mass exodus of gas, or "explosion" of bubbles. This also explains why soda goes flat. Given enough time, the CO 2 will all leave the solution, removing all of the dissolved gas which gives the soda its fizziness.
The carbonation is due to the presence of dissolved carbon dioxide gas. The gas exerts pressure when not dissolved, which can cause it to burst from its container if too much is released.
If exposed to air, the gas will slowly come out of solution and be released to the atmosphere, causing the drink to go flat. Answer 1: The bubbles in soda come from a gas called carbon dioxide that is dissolved into the soda. Still Curious? Does tapping on the top of an unopened soda can or bottle before you drink it reduce the risk of having a "soda explosion"?
If it does why does it do it? Henry - You probably know that soda is fizzy because it has lots of dissolved carbon dioxide in it. Normally, though, carbon dioxide is a gas. So when it's dissolved, it takes up less space than when it's a gas. If you shake a can of soda, you end up with tiny bubbles of carbon dioxide gas that stick to the inside surface of the can. If you open the can, the bubbles expand a lot and they push the soda right out with them, causing a "soda explosion. The concept of equilibrium.
Gradually, the rate at which gas molecules leave the neck and enter the soda equals the rate they leave the soda for the neck, and the soda is in equilibrium. The bottle achieves an equilibrium state after bottling and later on the shelf. How much carbon dioxide gas is in the bottle Henry's Law. The bottle temperature is constant; the gas is in equilibrium and the bottle contains a given gas-soda combination - namely the bottled soda. So we can apply Henry's Law, which says that in this case, the amount concentration of dissolved gas in the soda is proportional to the pressure of the gas in the bottle's neck above the soda.
Since the neck gas pressure is double the atmospheric pressure, the bottle contains double the concentration of carbon dioxide gas as it would at one atmosphere - that is, two bottles of carbon dioxide gas.
Why the capped, quiescent bottle has no bubbles. The bottle has been sitting on the shelf for some time. We look at it and see no bubbles, because bubbles can only exist if their pressure is at least as great as the surrounding liquid. It takes work to make a bubble. But, since the bottle is in a state of relative rest, the pressure is the same the bottling pressure of two atmospheres all over, so no bubbles can form. How bubbles form when you shake the bottle. You might think the pressure inside the bottle increases when shaken, but it does not.
Something else causes the eruption of foam. Find out by a simple experiment. Stir a glass of soda with a spoon, and create a small whirlpool. There's a string of bubbles in the vortex. That's the mechanism. The pressure of a simple vortex decreases toward the centre. Bubbles form in the lower pressure. Why soda explodes out.
Back to our capped bottle.
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