I think this problem has problem

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The discussion revolves around the thermodynamics of rubber bands, particularly the enthalpy changes when they are stretched. A high school student questions the assertion that a rubber band has higher enthalpy when not pulled, arguing that pulling it generates heat due to work done on the band. Another participant clarifies that stretching the band initially cools it, but when released, heat flows back into the band, increasing its enthalpy. The conversation also touches on the idea of using stretched rubber bands as a makeshift refrigeration method. Overall, the thread explores the complex relationship between work, heat, and enthalpy in rubber bands.
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Hi guys! I'm a high school student in korea. I was doing homework then, i found that i couldn't understand sth.

When i pull a rubber band, that will make rubber molecules equall but also make them hot.
The problem said 'the entalpy of rubber band when you didnt pull has higher entalpy than you pulled'

Buttttt i think that i worked to the band, so the heat was from work.
It can't define the higher entalpy because of release of heat.

Did i wrong?
 
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Stretch the band and allow it to return to it's original temperature. When you relax the band heat flows into the band from it's surroundings. Therefore it's entalpy increases.
 
Hi wrrr95, http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

wrrrr95 said:
When i pull a rubber band, that will make rubber molecules equall but also make them hot.
Actually, stretching makes them cold. You could concoct a crude refrigerator by stretching rubber bands.
 
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