Question

Question: Use the microscopic interpretation of entropy from Section 13.2 to explain why the entropy change of the system in Problem 26 is positive.

Short answer

The solid compound, SiO₂ , decomposes into two compounds: solid Si and gaseous O₂ . The key factor here is the gaseous O₂ which will increase the entropy due to the nature of the gaseous state. This is why the entropy change is positive.

Step-by-step solution

Given data

The value of entropy,$∆\mathrm{S}°=+182.02\mathrm{J}{\mathrm{K}}^{\mathbf{-}\mathbf{1}}$

Concept of entropy

Entropy seems to be a state function that is incorrectly referred to as a system's "state of disorder." Entropy is a qualitative measure of how much the energy of atoms and molecules spreads out in a process, and it can be expressed in terms of a system's statistical probability or other thermodynamic characteristics.

Explanation of entropy

The "level" of randomness is referred to as the entropy.

Due to the molecules' freedom to move, collide with one another, etc., it is high for gases.

In other words, their randomness is higher (entropy).

Although the particles in liquid compounds can still move, there is less unpredictability because of the greater link between them than there is in gaseous compounds.

The least amount of randomness occurs when discussing solid substances. The particles are fixed in a rigid structure, preventing random movement or allocation. This indicates that their randomness is decreased (entropy).

Conclusion

The solid compound, SiO₂, decomposes into two compounds: solid_, and gaseous O₂ .The key factor here is the gaseous O₂ which will increase the entropy due to the nature of the gaseous state. This is why the entropy change is positive.