You are high up in the mountains and boil water to make some tea. However, when you drink your tea, it is not as hot as it should be. You try again and again, but the water is just not hot enough to make a hot cup of tea. Which is the best explanation for this result? (a) High in the mountains, it is probably very dry, and so the water is rapidly evaporating from your cup and cooling it. (b) High in the mountains, it is probably very windy, and so the water is rapidly evaporating from your cup and cooling it. (c) High in the mountains, the air pressure is significantly less than \(101.3 \mathrm{kPa}\), so the boiling point of water is much lower than at sea level. (d) High in the mountains, the air pressure is significantly less than \(101.3 \mathrm{kPa}\), so the boiling point of water is much higher than at sea level.

Step by step solution

01

Eliminate explanations related to evaporation

First, let's examine explanations (a) and (b). Both explanations involve the rapid evaporation of water from the cup, which cools the water. While it is true that dry and/or windy conditions could cause water to evaporate, neither of these factors would affect the boiling point of the water or the actual temperature of the tea. So, we can eliminate explanations (a) and (b).

02

Understand the relationship between air pressure and the boiling point of water

Now let's focus on explanations (c) and (d), which both involve changes in air pressure and their effect on the boiling point of water. From science principles, we know that the boiling point of water decreases as air pressure decreases. The boiling point of water at normal atmospheric pressure (\(101.3 \mathrm{kPa}\)) is \(100 ^{\circ}\mathrm{C}\). At higher altitudes, air pressure decreases, so the boiling point of water is expected to be lower.

03

Choose the correct explanation

With our understanding of how air pressure and the boiling point of water are related, we can now evaluate explanations (c) and (d). - (c) High in the mountains, the air pressure is significantly less than \(101.3 \mathrm{kPa}\), so the boiling point of water is much lower than at sea level. - (d) High in the mountains, the air pressure is significantly less than \(101.3 \mathrm{kPa}\), so the boiling point of water is much higher than at sea level. Since we know that the boiling point of water decreases as air pressure decreases, the best explanation for the unusual behavior of boiling water at high altitudes is explanation (c).

Unlock Step-by-Step Solutions & Ace Your Exams!

• Full Textbook Solutions

  Get detailed explanations and key concepts

• Unlimited Al creation

  Al flashcards, explanations, exams and more...

• Ads-free access

  To over 500 millions flashcards

• Money-back guarantee

  We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!