Difference between coffee cup calorimetry and bomb calorimetry

[sillyjoe]

EK says:

"Bomb calorimeters measure energies; coffee cup calorimeters measure enthalpies."

Can someone please explain how there setups allow for different measurements?

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[lumpyduster]

Bomb calorimeters measure the heats of combustion. Because combustion results in gas formation (CO2/maybe H2O vapor), you can't use a coffee cup calorimeter since gas will escape. That's basically the only difference I can think of. I'm not sure why they made a distinction between energy and enthalpy. I may have misunderstood something.

 

[Gauss44]

Bomb calorimeters are NOT flexible and don't exchange heat with the environment so they can measure a pressure change and temperature change.

Coffee cups are at constant pressure.