Entropy of universe

[JustinHorriat_4f]

Does anyone have an explanation on why it is a spontaneous process if the change in entropy of the universe is +? Why is this favorable.

[Althea Zhao 1B]

The universe favors disorder. The textbook has a good example: it's a lot easier for heat to leave a block of metal than enter it because in order for it to enter the block of metal, it has to be concentrated and directional.

[gconcha]

Since represents a perfectly ordered material (aka equilibrium), a positive value for S means that the system has excess energy of some sort that will dissipate through heat, work, phase change, etc.

Therefore, since the system will want to somehow decrease its energy to reach a more stable state, it will lead to a spontaneous process.

[Ashley Fang 2G]

Adding on, a reaction can be spontaneous even when delta S is negative if delta H is negative enough, as long as the delta G value is negative.
delta G = delta H - T(delta S)