Calculating Change in Entropy for Water Vaporization at 100oC

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The discussion focuses on calculating the change in entropy for 50g of water vaporizing at 100°C, using the latent heat of vaporization, which is 540 kcal/kg. Participants clarify that heat is indeed absorbed during the vaporization process, contradicting the initial assumption of zero heat change. To find the entropy change, the latent heat must be used in conjunction with the mass of water being converted to steam. The correct approach involves applying the formula for entropy change, which incorporates both the heat absorbed and the temperature at which the phase change occurs. Understanding these principles is crucial for accurately calculating the entropy change during the vaporization of water.
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Homework Statement


The latent heat of vaporization for water is 540 kcal/kg. By how much does the entropy of 50g of water at 100oC change if the water is very slowly converted into steam at 100oC?


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The Attempt at a Solution


would it be 0 heat change plus the 540? = 540 total?
 
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No, it's not zero heat change. Certainly some heat enters the water to make it steam. How would you use the latent heat of vaporization to find out how much?
 
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