The sign of heat "q" is positive for a system when:
Correct answer: B. Heat flows from surrounding to system:
- A. The temperature of system drops
- B. Heat flows from surrounding to system:
- C. Heat flows from system to surrounding.
- D. No flow of heat between system to surrounding
Explanation
This is the definition of an endothermic process. The system absorbs heat, so q is positive.
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About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
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