How Does Entropy Vary with Temperature for Chemical Reactions?

In summary, the task is to calculate the temperature-dependent entropy and entropy for the reaction CH4 + 2 O2 = CO2 + 2 H2O using the given data for the specific heat capacities and entropies at 298K. The entropy values for CH4, O2, CO2, and H2O are 186.2, 205.6, 213.6, and 188.7 J/Kmol, respectively. The specific heat capacities for each substance are also provided in terms of temperature. The question is how entropy changes with temperature in this reaction.
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Homework Statement


As you know it's finals time and I desperatly need help with one physics task (it's not my main subject, but I still have to pass it -.-). Here it is: According to data below count temperature-depended entropy and entropy itself for reaction: CH4 + 2 O2 = CO2 + 2 H2O CH4: ΔS=186,2 [J/Kmol], Cp=14,15+75,5∙10-3 T-180,0∙10-7 T2 [J/Kmol] O2: ΔS= 205,6 [J/Kmol], Cp=25,72+12,98∙10-3 T-38,6∙10-7T2 [J/Kmol] CO2: ΔS=213,6 [J/Kmol], Cp=26,0+43,5∙10-3 T-148,3∙10-7 T2 [J/Kmol] H2O: 188,7 [J/Kmol], Cp=30,36+9,61∙10-3T+11,8∙10-7 T2 All reagents are gases, and the given values are for 298K.
 
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How does entropy vary with temperature?
 

FAQ: How Does Entropy Vary with Temperature for Chemical Reactions?

What is temperature-dependent entropy?

Temperature-dependent entropy refers to the change in the amount of disorder or randomness in a system as the temperature changes. It is a measure of the degree of randomness or chaos within a system and is directly related to the amount of energy in a system.

How is temperature-dependent entropy related to the second law of thermodynamics?

The second law of thermodynamics states that the total entropy of a closed system always increases over time. Temperature-dependent entropy is a manifestation of this law, as an increase in temperature leads to an increase in the disorder and randomness within a system, thus increasing the overall entropy.

How does temperature affect the entropy of a system?

As temperature increases, the motion and energy of particles within a system also increase. This leads to an increase in disorder and randomness, resulting in a higher entropy. Conversely, as temperature decreases, the motion and energy of particles decrease, leading to a decrease in entropy.

Can temperature-dependent entropy be reversed?

In general, no. The second law of thermodynamics states that entropy always increases over time, and it is highly improbable for a system to decrease in entropy without some external intervention. However, there are some cases, such as in living organisms, where entropy can be temporarily decreased by expending energy.

How is temperature-dependent entropy used in practical applications?

Temperature-dependent entropy is used in various fields, such as chemistry, physics, and engineering, to understand and predict the behavior of systems. It is an essential concept in thermodynamics, which is crucial for designing and improving energy systems, engines, and other technologies.

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