• Boiling points are affected by external pressure.
  • At higher altitudes, the atmospheric pressure is lower.
  • Pressure cookers do not allow the vapor to escape and the vapor pressure increases.
  • The effect of decreased air pressure can be demonstrated by placing a beaker of water in a vacuum chamber.
  • At a low enough pressure, about 20 mmHg, water will boil at room temperature.
  • The boiling point of water is 100°C at sea level.
  • At the summit of Mt.
  • Everest, water boils at only 70°C.
  • Use the resource below to answer the questions that follow.
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