system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When rice is boiling over, why do the bubbles immediately go down when you lift the lid?
gpt
The starch from the rice allows the water to form bubbles, but not very strongly, so typically the high pressure in the bubble will cause them to burst immediately, but when the lid is on the pot, the hot vapor and air increase the pressure in the air in the pot and lowers the imbalance in pressure, meaning the ambient air pressure is similar to the pressure inside that bubbles, so they don't burst. Opening the lid lowers the pressure, creates an imbalance and causes the bubbles to burst.