In each of the following pairs, which compound would you expect to have the higher standard molar entropy: (a) C2H2(g) or C2H6(g)? (b) CO2(g) or CO(g)?

Verified step by step guidance

1. Step 1: Understand that standard molar entropy (S°) is a measure of the amount of disorder or randomness in a system. Generally, more complex molecules and those with more atoms have higher entropy.
2. Step 2: For part (a), compare C2H2(g) and C2H6(g). Consider the molecular structure and the number of atoms in each compound. C2H6(g) has more atoms and is more complex than C2H2(g), which suggests it might have higher entropy.
3. Step 3: For part (b), compare CO2(g) and CO(g). Look at the molecular structure and the number of atoms. CO2(g) has more atoms than CO(g), which typically leads to higher entropy due to increased complexity and more possible microstates.
4. Step 4: Consider the phase of the compounds. Both pairs are in the gaseous state, so phase does not affect the comparison in this case.
5. Step 5: Conclude that in both comparisons, the compound with more atoms and greater molecular complexity is expected to have the higher standard molar entropy.