Calculating change in entropy with °C or K.

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When calculating the change in entropy using the equation dS = CVln(Tf/Ti), temperatures must be in Kelvin, not Celsius. Celsius can only be used for calculating temperature differences (ΔT). Converting to Kelvin is essential to ensure accurate results in thermodynamic calculations. The discussion emphasizes the importance of using the correct temperature scale for entropy calculations. Accurate unit conversion is crucial for proper thermodynamic analysis.
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Homework Statement

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I was given a graph in the PV plane of a cyclic process and asked to find some quantities, one of them is the change in entropy for the system. I just had a question about the units.

Homework Equations


dS = CVln(Tf/Ti)

The Attempt at a Solution


The data was given in Celsius, should I convert to kelvin when I put it into this equation?
 
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rmiller70015 said:
should I convert to kelvin
Absolutely.:wink:
 
The only time you can use °C is when you calculate a ΔT.
 
Thank you everyone.
 

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