Question

From the following information, determine ΔS°298 for the following:

a) N(g) + O(g)⟶NO(g) ΔS°298 = ?

b) N₂(g) + O₂(g)⟶2NO(g) ΔS°298 = 24.8 J/K

c) N₂(g)⟶2N(g) ΔS°298 = 115.0 J/K

d) O₂(g)⟶2O(g) ΔS°298 = 117.0 J/K

Answer 1

The standard entropy change (ΔS°298) for the reaction N(g) + O(g) → NO(g) can be determined using Hess's Law and the given standard molar entropies for related reactions. Combine these given values, considering the stoichiometry, to calculate the desired entropy change.

Step-by-step explanation:

To determine the standard entropy change (ΔS°298) for the reaction of nitrogen (N) and oxygen (O) to form nitric oxide (NO), you can use the standard entropy values for each species and apply Hess's Law. Here's how you could approach the problem:

1. Write down the given entropy changes for the reactions and the standard molar entropy values for individual gases.
2. Determine the overall entropy change for the formation of NO from elemental nitrogen and oxygen.
3. Apply Hess's Law to add or subtract the entropy changes of known reactions to get the desired reaction's entropy change.

For example, given the reactions and ΔS°298 values:

• N2(g) + O2(g) → 2NO(g), ΔS°298 = 24.8 J/K
• N2(g) → 2N(g), ΔS°298 = 115.0 J/K
• O2(g) → 2O(g), ΔS°298 = 117.0 J/K

Using these values, you would combine and manipulate them to derive the entropy change for the reaction N(g) + O(g) → NO(g), keeping in mind the stoichiometry of each reaction.