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Fifty grams of water at 0°C are changed into vapor at 100°C. What is the change in entropy of the water in this process?

a) 186.3 J/K, -
b) -186.3 J/K, -
c) 186.3 J/K, 93.15 J/K
d) -186.3 J/K, 93.15 J/K

User Kel
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Final answer:

The change in entropy of the water when it changes from liquid to vapor can be calculated using the formula ΔS = Q/T, where ΔS is the change in entropy, Q is the heat added to the system, and T is the temperature in Kelvin. In this case, 50 grams of water at 0°C is being changed into vapor at 100°C. The heat added can be calculated using the formula Q = mL, and the temperature change is 100°C - 0°C = 100 K. Substituting the values into the entropy formula, the change in entropy of the water is 167.5 J/K.

Step-by-step explanation:

The change in entropy of the water can be calculated using the formula ΔS = Q/T, where ΔS is the change in entropy, Q is the heat added to the system, and T is the temperature in Kelvin.

In this case, 50 grams of water at 0°C is being changed into vapor at 100°C. The heat added, Q, can be calculated using the formula Q = mL, where m is the mass of the water and L is the latent heat of vaporization. Assuming the latent heat of vaporization is 335 J/g, the heat added is 50 g x 335 J/g = 16,750 J.

The temperature change, T, is 100°C - 0°C = 100 K.

Substituting the values into the entropy formula, ΔS = 16,750 J / 100 K = 167.5 J/K. Therefore, the change in entropy of the water is 167.5 J/K.

User Joews
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