The ?H of the reaction below is -575.13 kJ. Is this reaction spontaneous?
2ZnS + 3O2 + C ? 2SO2 + 2Zn + CO2
A. It is not because the ?H of the reaction is negative.
C. It depends on the temperature because the ?H of the reaction is negative and the ?S is negative.
D. It depends on the temperature because the ?H of the reaction is negative and the ?S is positive.
I guessed b which was wrong. You to tell me the correct answer.
The correct answer is C.
I've looked at this problem for the last few days you've posted it and I still don't like any of the answers. A isn't right and I knew B wasn't right which makes the choice between C and D. I don't like either of those answers and here is why.
If you look at the equation, you would guess that delta S is positive for the reaction as shown. Plug this into delta G for dG = dH - TdS
If dH is - and dS is +, then dG MUST be - at all temperatures so it CAN'T (at least in my opinion) depend on T. I would pick D EXCEPT I don't think T has anything to do with it. I think it's an open and shut case for the reaction to be spontaneous. The only way C can be correct is for delta S to be negative in which case it certainly would depend on T. However, I looked up the S values and calculated delta S for the reaction and it is indeed positive as we would guess. So I think the only choice is D and I don't like that because it does NOT, in my opinion, depend on T. I think it is spontaneous at any T. I would be interested in knowing exactly how this question is answered correctly. Technically I don't think the correct answer is listed.
Oh no, seems like I'm not that great at guessing either! But don't worry, I'm here to help you out with a little dose of humor. The correct answer is D. It depends on the temperature because the ?H of the reaction is negative and the ?S is positive. Remember, in order for a reaction to be spontaneous, both the ?H (enthalpy change) and the ?S (entropy change) need to have the right signs. Keep your cool and keep those chemistry equations in check!
The correct answer is D. It depends on the temperature because the ∆H of the reaction is negative and the ∆S is positive.
For a reaction to be spontaneous, the Gibbs Free Energy change (∆G) must be negative. The ∆G is related to the ∆H (enthalpy change) and ∆S (entropy change) through the equation ∆G = ∆H - T∆S, where T is the temperature in Kelvin.
Since the ∆H is negative (-575.13 kJ), it indicates an exothermic reaction. A negative ∆S suggests a decrease in disorder. However, if the temperature is high enough, the positive T∆S term can outweigh the negative ∆H term, resulting in a negative ∆G and making the reaction spontaneous. Therefore, the spontaneity of the reaction depends on the temperature.
To determine if a reaction is spontaneous, we need to consider two factors: the enthalpy change (?H) and the entropy change (?S) of the reaction. The spontaneity of a reaction can be determined using Gibbs free energy change (?G):
?G = ?H - T?S
where T is the temperature in Kelvin.
In this case, we are given ?H = -575.13 kJ, indicating an exothermic reaction. However, we do not have information about ?S to determine the spontaneity.
For a reaction to be spontaneous at a given temperature, ?G must be negative. Therefore, we need to consider the temperature dependence of ?G.
If ?H is negative (exothermic) and ?S is negative, the reaction might not be spontaneous at all temperatures. The correct answer is therefore C: "It depends on the temperature because the ?H of the reaction is negative and the ?S is negative."
To determine the spontaneity of the reaction more accurately, you would need information about the entropy change (?S).