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Question
A mixture of fuel and oxygen is burned in a constant-volume chamber surrounded by a water bath. It was noticed that the temperature of water is increased during the process. Treating the mixture of fuel and oxygen as the system,
- Has heat been transferred?
- Has work been done?
- What is the sign of ∆U?
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Solution
- The heat from the chamber has been transferred to the water bath.
- The system (the mixture of fuel and oxygen) does no work because its volume does not change.
- There is an increase in the water's temperature. Therefore, ΔU is positive for water. For the system (the mixture of fuel and oxygen), ΔU is negative.
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