First Law Of Thermodynamics
A system absorbs 250 J of heat and does 150 J of work. The change in internal energy of the system is:
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About This Question
- Subject
- chemistry
- Chapter
- chemical thermodynamics
- Topic
- first law of thermodynamics
- Difficulty
- Easy
- Year
- 2025
Solution
Correct Answer:
100 J
According to the First Law of Thermodynamics (IUPAC convention): ΔU=q+w
- q: Heat absorbed by the system =+250 J
- w: Work done by the system =−150 J (system losing energy to surroundings) ΔU=250+(−150)=100 J
- The internal energy of the system increases by 100 J because heat gain exceeds work output.
This easy difficulty chemistry question is from the chapter chemical thermodynamics, covering the topic of first law of thermodynamics. It appeared in the 2025 exam.
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