Spontaneous [ENDORSED]

[Ju-Wei Wang 1I]

In a problem, how are we supposed to determine whether a reaction/process is spontaneous or not? I know you can figure it out when given Gibbs free energy, but what other way can be used to figure this out?

[Varsha Sivaganesh 1A]

Well in class, Lavelle mentioned that in any spontaneous process, there is an increase in entropy. However, I'm not sure if that means ALL spontaneous processes have a positive

[Susie Lee 2I]

Can someone briefly explain what it means to have a spontaneous process?

[Diane Bui 2J]

A spontaneous process means that it has the tendency to occur naturally without an outside force acting on it.

[Tiffany 1B]

Yeah so with spontaneous processes the entropy does increase so I think you would probably be able to assume that a positive delta S means spontaneous. Although Gibbs free energy might be a more definite way...

[Felicia Fong 2G]

An example for a spontaneous process would be a ball falling down a hill. This occurs naturally. A non spontaneous process would be a ball rolling uphill, which wouldn't occur on its own.

[Chem_Mod]

Spontaneity is dependent on the value of the Gibb's free energy for a process. Spontaneous processes will have a negative value. Just because a process is exothermic or increases entropy does not mean that it is spontaneous. For example, melting ice increases entropy, but ice will not melt below 0 C.