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Calculate the standard change in entropy for the reaction.

2NH3(g)+2O2(g) → N2O(g)+3H2O(g)


–9.6 J/K

811.2 J/K

10.8 J/K

User Wsanville
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Answer:

To calculate the standard change in entropy for the reaction, we need to consider the difference in entropy between the products and the reactants.

The balanced equation for the reaction is:

2NH3(g) + 2O2(g) → N2O(g) + 3H2O(g)

The standard change in entropy (ΔS°) can be calculated using the formula:

ΔS° = ΣS°(products) - ΣS°(reactants)

Where ΣS° represents the sum of the standard molar entropies of the species involved.

Looking up the standard molar entropies (S°) for each species involved in a reliable source, we find:

S°(NH3) = 192.77 J/(mol·K)

S°(O2) = 205.15 J/(mol·K)

S°(N2O) = 219.62 J/(mol·K)

S°(H2O) = 188.72 J/(mol·K)

Now we can calculate the standard change in entropy:

ΔS° = [ΣS°(products)] - [ΣS°(reactants)]

= [S°(N2O) + 3S°(H2O)] - [2S°(NH3) + 2S°(O2)]

= [219.62 J/(mol·K) + 3 * 188.72 J/(mol·K)] - [2 * 192.77 J/(mol·K) + 2 * 205.15 J/(mol·K)]

= 811.2 J/K

Therefore, the standard change in entropy for the reaction is 811.2 J/K.

User Paul Schroeder
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