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Due to lower atmospheric pressure at high altitudes, water boils at 92°C instead of 100°C. How will this difference affect cooking times? How will it affect the time needed to boil spaghetti noodles as compared to the amount of time needed at sea level? 1)It will be longer? 2) It will be shorter? 3) It will be the same?

User JEricaM
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2 Answers

5 votes

Answer:

A: It will be longer

User Ji ASH
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Answer:

Considering that water boils at 92ºC, the water will boil and dry before the food has finished cooking. So, the time needed will be shorter.

Step-by-step explanation:

The boiling temperature value of water, other liquids and solutions is influenced by atmospheric pressure. The higher the altitude, the lower the boiling point. For example, Mount Everest is in the Himalayan Mountain Range, whose altitude is 8848m and its atmospheric pressure is 240 mmHg. At this location, the water boils much faster than at sea level, boiling at approximately 71 °C.

When we put the water to heat, the energy received by the molecules enables them to pass into the vapor state. Initially we can see at the bottom of the container the formation of water vapor bubbles, and only after receiving more energy in the form of heat do these bubbles rise and are released on the surface, boiling. The bubbles are at the bottom of the container because atmospheric pressure exerts a force on the surface of the liquid, as if pushing the vapor bubble downward. The pressure within the bubble increases and increases until it equals atmospheric pressure and thus rises to a boiling point. The temperature at the time this occurs is the boiling point.

Thus, the higher the pressure on the surface, the more difficult it will be to supplant it and the liquid to boil, so the boiling point will be higher. On the other hand, if the pressure is lower, it will be easier to boil and the boiling point will be lower.

User Tlrobinson
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