Final answer:
Water boils at a higher temperature when the pressure is increased above 1 atm, such as in a pressure cooker, due to increased energy needed for vapor molecules to escape condensation. At higher elevations, water boils at lower temperatures due to decreased atmospheric pressure.
Step-by-step explanation:
It is indeed true that water boils at a higher temperature at higher pressure. At sea level, the standard atmospheric pressure allows water to boil at 100°C. However, when the atmospheric pressure is increased above 1 atm, for instance, using a pressure cooker, the boiling point of water also increases.
This occurs because the external pressure forces vapor molecules to condense, requiring the molecules to have greater kinetic energy to escape and become vapor. This is why the boiling temperature rises gradually as pressure increases. Conversely, at higher elevations, such as in Denver or on the summit of Mt. Everest, the atmospheric pressure is lower, so water boils at temperatures lower than 100°C.
The relationship between pressure and boiling point is crucial in various applications, including cooking. A lower boiling point at high altitudes means that cooking times must be adjusted, as food will cook slower due to the lower temperature at which water boils.
On the other hand, pressure cookers leverage the increased pressure to raise the boiling point of water and cook food faster. This has significant implications for recipes, cooking times, and even the operation of machinery that relies on boiling points.