Entropy and Temperature
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Entropy and Temperature
Why does delta S decrease when temperature increases? I understand it in terms of the equation of delta S because temperature is on the denominator, I just don't understand it conceptually. Can someone please explain this?
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Re: Entropy and Temperature
Hi, the way that I think about this is that, since delta S =q/T, an addition of heat makes a much bigger difference for the thermal vibration of a very cold substance than for an already hot one. For example, holding a flame up to a cup of hot tea won't really change its entropy much, but holding a flame up to an ice cube will change its entropy a lot (by melting it)
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Re: Entropy and Temperature
When the temperature changes more dramatically, there is more thermal motion which allows atoms to take on more random positions as they vibrate around each other. In a vapor, the atoms are moving faster and therefore will result in a much higher increase in entropy for a system.
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Re: Entropy and Temperature
The addition of thermal energy and thermal motion makes it so the molecules move around faster and can occupy more possible states. It's a little intuitive.
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Re: Entropy and Temperature
Adding heat to a system increases its kinetic energy and does cause more atomic vibrations that lead to an increase of disorder in the system, which corresponds to an increase in entropy. So calculating the change in entropy under a constant temperature heat transfer does seem like a direct proportion. However, this only means that the amount of entropy change is less at higher temperatures for a given heat transfer. Entropy increases with heat BUT, the change in entropy at lower temperatures will always be higher than the change in entropy at higher temperatures.
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