Question

Which of the following involve an increase in the entropy of the system? a. melting of a solid b. sublimation c. freezing d. mixing e. separation f. boiling

Short answer

The processes that involve an increase in entropy are: melting of a solid (a), sublimation (b), mixing (d), and boiling (f). These processes result in an increase in randomness or disorder within the system.

Step-by-step solution

a. Melting of a solid

Melting involves a solid turning into a liquid. During this process, the particles in the solid gain kinetic energy, causing them to move more freely. Therefore, the randomness of the system increases. Thus, melting of a solid results in an increase in entropy.

b. Sublimation

Sublimation is the process in which a solid transitions directly into a gas, bypassing the liquid state. In this process, the particles in the solid break their bonds and move independently as a gas. The randomness of the system increases during this transition. Thus, sublimation involves an increase in entropy.

c. Freezing

Freezing is the process of a liquid becoming a solid. As the liquid particles lose kinetic energy, they become more ordered, forming the rigid structure of a solid. Therefore, the randomness in the system decreases. Thus, freezing does not involve an increase in entropy.

d. Mixing

During the mixing process, two or more substances are combined into a mixture. The particles of different substances are distributed randomly, increasing the disorder in the system. Mixing, therefore, involves an increase in entropy.

e. Separation

Separation is the process of separating two or more substances from a mixture. This process results in a more ordered system, as the particles of different substances are arranged separately. Therefore, separation does not involve an increase in entropy.

f. Boiling

Boiling involves a liquid transitioning into a gas. In this process, the particles in the liquid gain enough kinetic energy to break their bonds and move freely as a gas. The randomness of the system increases during boiling. Thus, boiling involves an increase in entropy. In conclusion, the processes that involve an increase in entropy are: melting of a solid (a), sublimation (b), mixing (d), and boiling (f).