Question

Which of the following reactions would result in increased entropy?A. 2CO(g) + 2NO(g) → 2CO₂(g) + N₂(g)B. N₂(g) + 3H₂(g) → 2NH3(g)C. KNO3(s) → K+ (aq) + NO3-(aq)D. 2C0(g) + O₂(g) → 2C0₂(g)

Answer 1

Entropy is related to the degree of disorder of a process. If disorder increases, entropy increases.

Now, in a chemical reaction this disorder can be associated with the dissolution of a solid in a liquid, or by the increase in moles when the reaction is at the gaseous phase.

We have 3 reactions that occur in the gas phase, A, B, and D. All these reactions have as products less number of moles with respect to the reactants, so in these three reactions the entropy does NOT increase, it decreases

Reaction C refers to the dissolution of a solid reactant. This dissolution represents an increase in entropy.

Therefore, the answer will be: C. KNO3(s) → K+ (aq) + NO3-(aq)