Sodas go flat after being opened and even lose a bit of taste.
Sparkling waters, wines and, of course, soda pops fizz because of the carbon dioxide dissolved, at high pressures and low temperatures, in every can and bottle. Carbonation adds a weak acid that gives your Coca-Cola a little tang while acting as a preservative, as well.
When you pop the top, the pressure inside the can decreases, causing the CO2 to convert to gas and escape in bubbles . Let a can sit long enough before sipping and you will notice not only the lack of bubbly fizz but also the absence of the carbonic flavor.
Beverage chemistry may be the largest single market for carbon dioxide, but it's not the only one. Solid CO2 refrigerates better than ice from H20, and this solid carbon dioxide, or dry ice, is used to freeze foods.