Problem: For the following reaction, ΔH rxn = −120 kJ / mol-rxn and ΔS rxn = −150 J / mol-rxn•K:2NO(g) + O2(g) → 2NO2(g)At what temperatures will this reaction be spontaneous?Note: Remember that we can assume that the ΔH and ΔS values are approximately independent of temperature.Choose 1 answer:a. The reaction is never spontaneous, no matter what the temperature.b. The reaction is spontaneous when T < 800 K.c. The reaction is spontaneous when T > 800 K.d. The reaction is spontaneous at all temperatures.

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We are asked for the temperatures at which this reaction would be spontaneous.

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Problem Details

For the following reaction, ΔH rxn = −120 kJ / mol-rxn and ΔS rxn = −150 J / mol-rxn•K:

2NO(g) + O2(g) → 2NO2(g)

At what temperatures will this reaction be spontaneous?

Note: Remember that we can assume that the ΔH and ΔS values are approximately independent of temperature.

Choose 1 answer:

a. The reaction is never spontaneous, no matter what the temperature.

b. The reaction is spontaneous when T < 800 K.

c. The reaction is spontaneous when T > 800 K.

d. The reaction is spontaneous at all temperatures.

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