STEM与日常科技·英语30篇（3）

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相变潜热与烧水沸腾平台期

When water reaches 100°C at sea level, temperature stops rising—even with steady heat—until all liquid becomes steam.
That pause happens because energy flows not into raising temperature, but into breaking molecular bonds during phase change.
This stored energy is called latent heat: 2260 kJ per kilogram, over five times more than needed to warm water from 0°C to 100°C.
Steam burns are worse than boiling water burns precisely because steam releases all that latent heat instantly on skin.
Refrigerators exploit the reverse: compressing gas into liquid releases latent heat outside; expanding liquid into gas absorbs heat inside.
Geysers erupt when underground water absorbs latent heat from rock, builds pressure, then flashes to steam explosively.
Cooking pasta evenly depends on maintaining rolling boil—ensuring constant energy input matches latent heat demand.
Phase-change materials in building walls absorb daytime heat as they melt, then release it slowly at night—stabilizing indoor temperatures.