Final answer:
The statement is false; a reaction with a large decrease in entropy and absorption of heat (positive ΔH) can only be spontaneous at certain temperatures, where the TΔS term is small enough to result in a negative ΔG.
Step-by-step explanation:
False. If a reaction experiences a large decrease in entropy (negative ΔS) and absorbs a large amount of heat (endothermic, positive ΔH), the reaction will not be spontaneous at all temperatures. According to the Gibbs free energy equation (ΔG = ΔH - TΔS), the spontaneity of a reaction depends on both enthalpy and entropy changes, as well as the temperature. For a reaction to be spontaneous, ΔG must be negative. In the case of a reaction with a large decrease in entropy and heat absorption, the TΔS term must be small relative to the enthalpy term (ΔH) for ΔG to be negative. This can occur only under certain temperature conditions. An example is the freezing of water, which is spontaneous only below 273 K where the entropy reduction does not outweigh the enthalpy gain.