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Grade 10 Science · Problem type
When is it spontaneous?
Use this for “A reaction has ΔH > 0 and ΔS > 0. When is it spontaneous?”
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When is the change spontaneous?
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Assumptions
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ΔG = ΔH − TΔS, and a reaction is spontaneous when ΔG is below 0.
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The signs of ΔH and ΔS decide; when they pull opposite ways, the temperature settles it.
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Related lessons
Entropy, free energy and spontaneity
Main lesson
The temperature where it turns spontaneous
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Does entropy go up or down?
Use this for “Predict the sign of ΔS when a gas forms from a solid.”