Great question. There is lots of gas contained in fizzy drinks. And not just the gas you see you when you open the bottle! It’s dissolved in the liquid itself and is only released when you give it some energy, like shaking the bottle, making it warmer, or start to break up the liquid with acid.
That’s exactly what you’re doing when you drink it. You’re moving it around, warming it up, and exposing it to the acid in your stomach. So, the gas is released in your stomach and has to go somewhere! So it’s released through your mouth as a burp!
Interesting question rubaty! well, we know that fizzy drinks are basically sugar, flavoring, water, preservatives and most importantly, invisible carbon dioxide gas (the thing that makes soda bubbly). This gas is pumped into bottles at the bottling factory using tons of pressure. It’s this gas that builds up in your stomach and eventually has to come out… as a burp. hope that helps 🙂