JAMB - Chemistry (2024 - No. 25)
For chemical reaction to be spontaneous, ∆G must be
positive
negative
zero
equal to the enthalpy change
설명
A spontaneous reaction is a reaction that proceeds on its own in a given set of conditions, without the external addition of energy.
Gibbs Free Energy (∆G), is thermodynamic quantity which represents the amount of usable energy available in a system at constant temperature and pressure. A negative value for ΔG indicates a spontaneous process; a positive ΔG indicates a nonspontaneous process; and a ΔG of zero indicates that the system is at equilibrium.This is because it means the system is releasing free energy, moving towards a lower energy state, and thus the reaction can occur without external energy input; essentially, the products have less free energy than the reactants, making the process naturally favourable.