A thermos bottle works as follows. A hollow chamber surrounds most of the liquid, as shown in figure 1. In a good thermos bottle, the chamber contains almost no air. As a result, the heat flow between the liquid inside the thermos bottle and the surrounding environment is greatly reduced.
FIGURE 1
While hiking on a hot day, two chemistry students broke their thermos bottle. This sparked an argument about how best to keep their cold cans of juice from getting warm.
Chemistry student 1
We should wrap the cans in thick wool socks—the more socks, the better.
Chemistry student 2
No, it's better to make sure lots of air blows over the cans, so that the "breeze" keeps them cool. We should keep the cans unwrapped, and expose them to a breeze, perhaps by keeping the backpack partially open. (Just make sure no direct sunlight shines on the cans!)

1. | Even if the chamber of a thermos bottle contained a perfect vacuum, hot coffee in the thermos bottle would still cool off (though extremely slowly), due primarily to

A. | Conduction

B. | Convection

C. | Radiation

D. | None of the above

2. | A thermos bottle "works" primarily by reducing the heat flow due to

A. | Conduction

B. | Convection

C. | Radiation

D. | None of the above

3. | Chemistry student 1 wants to wrap the cold cans in thick wool socks. As compared to leaving the cans unwrapped, this plan will:

A. | Make the cans heat up more quickly than they otherwise would.

B. | Make no difference in how quickly the cans heat up.

C. | Make the cans heat up less quickly than they otherwise would.

D. | Prevent the cans from heating up at all.

4. | Chemistry student 2 wants to keep the backpack open, so that air flows over the cans. This plan will:

A. | Make the cans heat up more quickly than they would if the backpack were closed.

B. | Make no difference in how quickly the cans heat up.

C. | Make the cans heat up less quickly than they would if the backpack were closed.

D. | Prevent the cans from heating up at all.

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