Coffee cup, bomb calorimeter: Open, closed, or isolated?

[gauss44]

Is a coffee cup usually considered to be a closed system? Why or why not? Does it matter that steam or hot coffee may be evaporating? (I think the steam is usually considered to be an insignificant amount of matter, allowing classification to be a closed system, but am unsure.)

Is a bomb calorimeter an isolated system? Why or why not? Is the water inside of a bomb calorimeter generally considered to be part of the "surroundings?" (I think not, just checking.)

(I tried looking this up online and cannot find any definitive answer or actual examples that were adequately helpful.)

 

[Bystander]

This has the sound of homework: state the definitions/properties of open, closed, and isolated systems; apply those definitions/properties to the systems you've described.

 

[Bystander]

I guess you could project that onto any question in this forum. I sense a troll at work.

It's a very common pre-lab quiz question intended to determine whether you know the definitions of open, closed, and isolated systems.

If you don't know the definitions/properties/differences of open, close, and isolated systems, this turns into an endless game of "Well if that's "blank," then what's this?"

State them, apply them to each, and I'll be more than happy to tell you whether you've done so correctly, or explain to you where you've done so incorrectly, and what is incorrect.

 

[SteamKing]

If a coffee cup is a closed system, how are you supposed to drink the coffee? You don't need to go online to find the answer to this question.

 

[DeeNos]

I can provide a response to this question. A coffee cup can be considered a closed system because it is not exchanging matter with its surroundings. However, it is not a perfectly closed system because steam or hot coffee may be evaporating from the cup, which would result in a small amount of matter leaving the system. This may not significantly impact the overall classification of the system, but it is important to consider when conducting experiments.

On the other hand, a bomb calorimeter is typically considered an isolated system because it is designed to prevent any matter from entering or leaving the system. This is important for accurately measuring the heat released during a chemical reaction. The water inside the bomb calorimeter is generally considered part of the surroundings, as it is not involved in the reaction and is used to absorb the heat released.

It is worth noting that the classifications of open, closed, and isolated systems are not always black and white. In some cases, a system may have characteristics of more than one classification. It is important for scientists to carefully consider the properties of a system when conducting experiments and interpreting results.