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What happens when hot lava meets cold water?

Lava meeting water can leave rounded rock forms instead of the explosion a dramatic video might lead you to expect. The lava cools while the water takes up energy, and the result depends on how they meet, how quickly heat moves, and the surrounding pressure.

5–7 min

Questions you could explore

  • What can the shape of cooled lava reveal about its surroundings?
  • When might a crust change the contact between water and molten rock?

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4–5 min

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What happens when hot lava meets cold water? | Speech Topic | speaking.app