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A large and a small cast iron pan are compared. Which quantity is the same for both?
AThe heat capacity in joules per degree
BThe heat needed for a 50 degree rise
CThe specific heat in joules per gram degree
DThe mass of iron used to make the pan
Answer & Solution
Correct answer: C. The specific heat in joules per gram degree
1. The two pans are made of the same material but have different masses.
2. The heavier pan needs more energy for the same temperature rise, so its heat capacity is larger.
3. Dividing the heat by the mass as well removes that size effect.
4. Both pans then give 0.449 J per gram per degree Celsius.
5. So specific heat is the quantity that matches, since it depends on the material only.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 5 "Thermochemistry", section 5.1 Energy Basics_
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