## when doesn't a solid's temp change?

$\Delta S = \frac{q_{rev}}{T}$

Payton Kammerer 2B
Posts: 49
Joined: Tue May 01, 2018 3:00 am

### when doesn't a solid's temp change?

4F.3 (a) Calculate the change in entropy of a block of copper at 25 8C that absorbs 65 J of energy from a heater. (b) If the block of copper is at 100. 8C and it absorbs 65 J of energy from the heater, what is its entropy change? (c) Explain any difference in entropy change.

I understand how the book wants me to do this problem- q/T- but I am so confused as to how we can reasonably make the assumption that T doesn't change. It would have to be a BLOCK of copper to not have a temp change, right? Copper is a metal, so it conducts heat well, so has a low heat capacity. q=CdeltaT, a small amount of heat combined with a low heat capacity makes for a large temp change. What situations allow for this assumption to be reasonably made for metals?

Sahil Jog 1F
Posts: 126
Joined: Thu Jul 11, 2019 12:16 am

### Re: when doesn't a solid's temp change?

You're definitely correct. You would need to first calculate the temperature change of the copper as it absorbs 65 J of energy, and once you get that temperature, you would then calculate the change in entropy by plugging it into the entropy equation that deals with changes in temperature. Hope this helps.

Nick Fiorentino 1E
Posts: 102
Joined: Wed Sep 18, 2019 12:16 am

### Re: when doesn't a solid's temp change?

I'm sure it does change but for the purposes of this question I don't think it matters. That may be a topic addressed in more advanced classes but this class seems to simplify thermodynamics to a certain extent, because it is a really complicated topic