Reaction Spontaneity and Temperature

This applet shows how to predict reaction spontaneity based on standard enthalpy and entropy values.  Values which promote spontaneity (i.e. negative enthalpy, positive entropy) are shown in green, while resisting values (i.e. positive enthalpy, negative entropy) are shown in red.

Reaction 1 is exothermic but reduces entropy, making it spontaneous at low temperatures, but not at high temperatures.  Reaction 2 is endothermic and decreases entropy, and is therefore not spontaneous at any temperature.  Reaction 3 is exothermic and causes an increase in entropy, making it spontaneous at all temperatures.

Things to consider:

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