Constant Volume Condition

[Fernell_Orellana_3C]

Hello,

Is there any reason as to why bomb calorimeters always have constant volume? Will there be a scenario in which this condition could be different?

[Lucas Vu 2G]

The volume is constant in a bomb calorimeter because the structure of a bomb calorimeter is made such that the volume of it won't change under reactions inside of it.

[306250289]

the volume is fixed because it is sealed. no matter is getting into it and no pressure is causing the volume to change either

[anasofia]

Hi!
Constant volume (isochoric) conditions simplify the thermodynamic analysis of the system. When the volume is constant, changes in internal energy (ΔU) are directly proportional to the heat added or removed (q) from the system, so it makes energy by heat easier to measure. They are a closed system, so volume is constant, and work = Pext * change in volume, so if the change in volume is zero work is zero. For the bomb calorimeter they will always be closed systems, as having it open would cause a volume change, work would not be zero, and it would defeat the purpose of simplifying the analysis of energy change as heat. Hope this helps