What explains the key difference between a bomb calorimeter and a coffee cup calorimeter?

A coffee cup calorimeter is open to the atmosphere and is commonly used for reactions in aqueous solution. A bomb calorimeter holds the sample in a sealed, rigid chamber, so it can measure heat changes for reactions that do not occur in water. Therefore, the key difference is the separate chamber and ability to study non-water reactions.

AI-written and checked against the verified answer.