Calorimetry
A 50 g sample of water at 20°C is mixed with 50 g of water at 80°C. The final temperature of the mixture is:
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About This Question
- Subject
- chemistry
- Chapter
- chemical thermodynamics
- Topic
- calorimetry
- Difficulty
- Easy
- Year
- 2025
Solution
Correct Answer:
50°C
Assume there is no heat loss to the surroundings. HeatLostbyHotWater=HeatGainedbyColdWater m1cp(Thot−Tf)=m2cp(Tf−Tcold)
- m1=m2=50 g
- cp cancels out. 80−Tf=Tf−20 2Tf=100⟹Tf=50∘C
- Since masses and substances are identical, the final temperature is the simple arithmetic mean.
This easy difficulty chemistry question is from the chapter chemical thermodynamics, covering the topic of calorimetry. It appeared in the 2025 exam.
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