Gibb's Free Energy: Spontaneous Reactions at High Temperatures

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A reaction is considered spontaneous if its Gibbs Free Energy change (Delta G) is negative, as indicated by the formula Delta G = Delta H - (T*Delta S). In the example provided, the reaction of H2O(g) to CO(g) and H2(g) shows a negative Delta G at 1173 Kelvin, suggesting spontaneity. However, the discussion raises the question of whether this spontaneity holds at extremely high temperatures, such as 999999999999999999999999 degrees Kelvin. Theoretical considerations suggest that while the calculation may indicate spontaneity, such extreme temperatures are not practically achievable and would likely lead to other reactions or effects that could alter the system's behavior. Thus, while the mathematics may imply spontaneity at any temperature, real-world conditions limit the practical significance of such high temperatures.
rajakavuru
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Hello,
If a reaction is spontaneous when calculated using Gibb's Free Energy formula,
Delta G = Delta H - (T*Delta S)

Does it mean the reaction will occur at impossible temperatures even (such as 999999999999999999999999 degrees Kelvin)

for ex:
H2O(g) C(s) --> CO(g)+H2(g)
Delta H = 135.5 kJ
Delta S = .1488 kJ
T = 1173 Kelvin

Delta G = -39 (if delta G is negative, the reaction is spontanious, according to Gibb's Free Energy)

since this reaction is spontanious, will this occur at 99999999999999999 degrees kelvin even? (is this possible?)
 
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Theoretically, it is. But since you cannot achieve such a temperature, it has no practical significance.
 
No, it doesn't mean that. When temperature rises other effects/reactions tend to take place and they replace initial system.

http://en.wikipedia.org/wiki/Orders_of_magnitude_(temperature )
 
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