Question

A scientist climbs to a summit, and decides to leave some hot water for the next person to do so. He rinses out an iron saucepan, uses it to melt some snow, and continues to heat until the water boils.He fills an insulating flask (made from stainless steel, so it won’t rust) to the brim with the hot water, screws the lid on very tightly, and leaves it next to the summit. Unfortunately, the flask is only found 3 months later, and is of no use to the mountaineer who finds it.Explain all the reasons why the flask and its contents are of no use to the mountaineer.

Answer 1

The flask and its contents are of no use to the mountaineer because the hot water would have cooled and frozen over time, there would be heat loss due to improper insulation, and the tightly sealed flask could have caused a pressure build-up.

Step-by-step explanation:

The flask and its contents are of no use to the mountaineer for several reasons:

1. Cooling and Freezing: Over the course of 3 months, the hot water in the flask would have cooled down to the surrounding temperature, which in a summit environment is often below freezing point. This means that the water would have frozen, rendering it unusable.
2. Heat Transfer: The flask was not properly insulated, and since heat transfer occurs from hot to cold objects, the hot water would have lost a significant amount of heat to the surrounding environment, further hastening the cooling and freezing process.
3. Pressure Build-up: The flask was tightly sealed, which would prevent the vapor formed from the hot water from escaping. As the water cooled and turned into ice, the expanding ice would have caused increased pressure inside the flask. Eventually, the pressure would have become too high, potentially causing the flask to explode.

Answer 2

In this example, the scientist made sure to store the bolied water in the flask, but it was not enough for the mountaineer to find it in conditions that the scientist left it. This was because a long time passed and the hot water began to lose heat by conduction through the flask.

Conduction is a way of heat transfer that is caused by direct contact between molecules (in this case, the molecules of the hot water, and the molcules of the walls of the flask), due to the differemce in temperature (hot indside the flask, and cold outside the flask).