Final answer:
The correct answer is c. The compounds CO2, SO2, and C3H8 should be arranged in order of increasing entropy based on their molecular complexity and physical states. CO2 as a simple molecule has the lowest entropy, SO2 is more complex with slightly higher entropy, and C3H8, being the most complex, has the highest entropy. Therefore, the order is CO2 < SO2 < C3H8.
Step-by-step explanation:
The student's question involves arranging certain chemical compounds in order of increasing molar entropy at 298 K. Molar entropy is a measure of the amount of energy released or absorbed during a process. Substances with more complex molecular structures typically have higher molar entropy because they have more available microstates. From the given options, to determine the correct order, we need to consider factors such as the physical state of matter, molecular complexity, and bonding.
- Crystalline solids have the lowest entropy because they are highly ordered.
- Liquids have higher entropy than solids due to increased molecular motion.
- Gases have the highest entropy among the states of matter due to the greatest amount of molecular disorder.
Gases tend to have higher molar entropy than liquids and solids because of their greater disorder. Additionally, larger and more complex molecules have higher entropies than smaller and simpler ones.
C3H8 (propane)
is a larger and more complex molecule than either
CO2 (carbon dioxide)
or
SO2 (sulfur dioxide)
, hence it should have the highest entropy. CO2 is a linear molecule while SO2 has a bent shape but similar molar masses; however, SO2 is slightly more complex due to its bonding angles, which provides more microstates and therefore a higher entropy.
Thus, the correct order of increasing entropy would likely be CO2 < SO2 < C3H8. This is because CO2 is a simple linear molecule, SO2 is more complex, and C3H8 is the most complex of the three.