|MadSci Network: Other|
The answer to your question is based on the laws of chemistry and physics. CO2 gas is dissolved in the beer. The bottle is under pressure and probably cold. The amount of CO2 dissolved in the beer is directly dependent on the pressure and the temperature. The more pressure, the more dissolved CO2. The colder the beer, the more dissolved CO2. As the bottle is opened, the pressure in the bottle is changed to atmospheric pressure. This causes a change in the solubility of the CO2 in the beer. The CO2 gas in a bubble moves upwards to be released into the atmosphere. As the bubbles of gas move to the atmosphere they coalesce (come together) and form larger bubbles which contain a larger volume of gas. This larger volume of gas is subject to less pressure as it moves upwards and begins to pick up speeed. A good example of pressure in a liquid is felt when you dive to the bottom of a pool. You feel more pressure on your ears the deeper that you dive. If you reverse this effect, there is less pressure at the surface of the pool. A good explanation of the laws and principles at work here can be found in the following link: http://www.truetex.com/carbonation.htm I hope that this answers your question. Carbonation is Cool
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