How much energy does it take to heat a block of ice

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To calculate the energy required to heat a 35 g ice cube from -15°C to steam at 117°C, the specific heats and phase changes must be considered. The calculations involve raising the ice temperature to 0°C, melting it to water, heating the water to 100°C, vaporizing it to steam, and finally raising the steam temperature to 117°C. The initial calculation of 114,734 J was incorrect due to an oversight in the temperature increase of the steam, which only needs to rise 17°C instead of 100°C. Correcting this error will yield the accurate total energy required. Accurate calculations are crucial in thermodynamic problems to ensure correct results.
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Homework Statement


How much energy is required to change a 35 g ice cube from ice at −15 C to steam at 117 C?
The specific heat of ice is 2090 J/kg * C, the specific heat of water is 4186 J/kg * C, the specific heat of stream is 2010 J/kg * C, the heat of fusion is 3.33 × 10^5 J/kg, and the heat of vaporization is 2.26 × 10^6 J/kg.
Answer in units of J.


Homework Equations



Q=m*L
Q=m*c*\DeltaT

The Attempt at a Solution


35g*15C*2090J/kg*C - heat to raise ice's temp. to freezing
+ 3.33 * 10^5 J/kg *35g - heat to melt ice into water
+ 100C *4186J/kg*C *35g - heat to raise water temperature to boiling
+ 2.26*10^6 J/kg* 35g - heat to boil water into vapor
+ 2010 J/kg*C *117C *35g - heat to make vapor rise to 117 C
=114734 J

I tried this answer and the program says it's incorrect, what am I doing wrong?
 
Physics news on Phys.org
The steam only has to rise 17C in temperature from 100C to 117C.
 
Thanks for your help... I completely missed that, I guess that's what I get for trying to do physics late at night. :)
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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