What is the outcome when ΔH is negative and ΔS is positive?

When the change in enthalpy (ΔH) is negative, it indicates that the reaction is exothermic; heat is released during the process. When the change in entropy (ΔS) is positive, it suggests that the disorder of the system increases, meaning the products of the reaction have more energy states available than the reactants.

In thermodynamics, the spontaneity of a reaction at a given temperature is determined by the Gibbs free energy change (ΔG), which is given by the equation:

ΔG = ΔH - TΔS

For a reaction to be spontaneous, ΔG must be negative. When ΔH is negative and ΔS is positive, the first term in the equation (ΔH) is a negative value and the second term (TΔS) is positive, since T (temperature) is always positive. This means that as the temperature increases, the negative impact of the positive ΔS term becomes more significant, but because ΔH is negative from the outset, this makes ΔG negative at all temperatures.

Therefore, with both conditions satisfied—negative ΔH and positive ΔS—the reaction is spontaneous across all temperatures. This leads to the conclusion that the reaction can occur spontaneously at any temperature, making the