A spontaneous process is when a reaction takes place naturally without the help of a catalyst. Similarly, a non-spontaneous reaction takes place with the help of a catalyst.
An example of a spontaneous reaction is a paper turning yellow overtime while a non-spontaneous reaction might be setting a piece of wood on fire.
Spontaneity can be calculated through
\Delta G^\circ=\Delta H^\circ - T\Delta S^\circ
Delta H stands for change in enthalpy and T delta S is change is entropy.
Delta G < 0 = Spontaneous reaction
Delta G > 0 = Non-Spontaneous
Delta G = 0 = At equilibrium.
Try out this problem using the formula above.
Methane gas reacts with water vapor to produce a mixture of carbon monoxide and hydrogen according to the balanced equation below.
\text_4(g)+\text_2\text(g) \rightarrow \text(g)+3\text_2(g)
The \Delta H^\circ for the reaction is +206.1 kJ/mol, while the \Delta S^\circ is +215 J/K • mol . Calculate the \Delta G^\circ at 25°C and determine if the reaction is spontaneous at that temperature.
I will comment the answer once you solve it!
