Can a reaction spontaneously happen without any energy input?
Thermodynamic free energy
Can a reaction spontaneously happen without any energy input?
Imagine you're trying to push a heavy box up a hill without any help; it's tough and tiring.
A spontaneous reaction is like pushing that box up the hill—it's easier if the hill is downhill (negative change in Gibbs free energy) or if you have a helper (positive entropy change) that makes the push easier.
Example
If the box is downhill, it moves by itself (negative Gibbs free energy), like a spontaneous reaction. If you have a helper (like an increase in entropy), it makes the uphill push (positive Gibbs free energy) easier.
Remember this
A spontaneous reaction happens when the Gibbs free energy change (ΔG) is negative, indicating that the reaction can occur without extra energy.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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