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Pressure changes the temperature of boiling

At ordinary sea-level pressure, pure water in an open pot boils at about 100°C: adding more heat just turns the liquid into steam faster. A sealed pressure cooker traps that escaping vapor, raising the pressure inside the pot so water can remain liquid at a higher temperature and cook tough food in a fraction of the time.

3–5 min

Questions you could explore

  • Why does the surrounding pressure matter to boiling?
  • How would altitude complicate a single temperature claim?

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Pressure changes the temperature of boiling | Speech Topic | speaking.app