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Pressure, dissolved gas, and a fizzy drink's bubbles

An unopened bottle of soda looks completely still, as if there were no gas inside the liquid at all. Twist the cap, however, and the sudden drop in pressure above the drink means the water can no longer hold as much dissolved carbon dioxide, allowing gas that was already hiding in solution to gather at microscopic rough spots and rise as bubbles.

3–5 min

Questions you could explore

  • Why can the surface of a glass change the pattern of bubbles?
  • What is the difference between releasing dissolved gas and making new gas?

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Pressure, dissolved gas, and a fizzy drink's bubbles | Speech Topic | speaking.app