On a very hot pan, water drops skate around and last longer than on a pan that is merely hot.
Why it is true
This is the Leidenfrost effect, described in 1756. Above about 200 °C, the underside of the drop evaporates instantly and forms a cushion of steam that insulates it from the metal. The drop floats and heats slowly instead of boiling away at once.
Source: American Physical Society
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This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.
