Why Does Soda Pop Fizz?
The bubbles in a soft drink are made by a tasteless gas called carbon dioxide gas. This bubbly gas gives the drink its tangy, sharp taste. Soft drink manufacturers add this tingling froth into your soda at high pressures—up to 1,200 pounds per square inch.
At the bottling plant, the gas is pumped into water, flavored with cola, orange, or any other flavor you might want. The bottle is then tightly capped. When you open the bottle, the pressure is released and the gas fizzes out.
This requires energy because in order for the gas to break free from the liquid it has to overcome the force holding the liquid together.
Soft drinks are called “soda pop” because the drink was once made with soda and because of the popping sound that the escaping gas made when the early cork bottle stoppers were removed.