Final answer:
The products have a higher entropy than the reactants in the reaction 2NH₃(g) → N₂(g) + 3H₂(g) because the products result in more gas molecules, thus increasing the disorder of the system.
Step-by-step explanation:
To answer which has higher entropy in the reaction 2NH₃(g) → N₂(g) + 3H₂(g), we are looking at the entropy change from reactants to products. Entropy is a measure of the disorder or randomness in a system. Considering the number of gas molecules before and after the reaction, the reactants consist of 2 molecules of NH₃(g), while the products consist of 1 molecule of N₂(g) and 3 molecules of H₂(g), totaling 4 molecules.
An increase in the number of gas particles generally corresponds to an increase in entropy due to more microstates becoming available for the configuration of the system. Therefore, the products have a higher entropy compared to the reactants because there are more molecules of gas produced, increasing the disorder.