Which of the following's the limiting case between spontaneous and non-spontaneous process.....
A) exothermic process
B) endothermic....
C) reversible .......
D) irreversible......

Question

Which of the following's the limiting case between spontaneous and non-spontaneous process.....
A) exothermic process
B) endothermic....
C) reversible .......
D) irreversible......

photon336 · Answer

@Empty

anonymous · Answer

Well what makes a reaction spontaneous or not? It all depends on the Gibb's free energy.

G=H-TS

When G < 0 it's spontaneous, and when G > 0 It's not spontaneous, that's by definition in thermodynamics but also it makes sense. The main thing to be aware of is that spontaneous doesn't mean "fast" it just means it happens on its own, however this can mean it takes super super slowly like years, like diamonds turning into graphite is spontaneous but we can't observe it over small time scales...

That being said, what is this equation? Well remember, ,exothermic and endothermic are actually special cases of what H can be, so the limiting cases are going to be when T and S combined with that particular choice of H will flip the sign on G.

Kinda confusing I know, so give it some time to sink in.

shikamaru11 · Answer

ok @Woodward Respected Sir :) and thanks for coming

photon336 · Answer

that question was worded strangely

anonymous · Answer

Haha I wouldn't say respected sir, I'm just some dude haha

shikamaru11 · Answer

I know @Photon336 Sir It's a strange one 
@Woodward Ok Dude I won't say next time :) Stay happy 
so what you think is the rite one I chose C.....
cause it's the difference between both......

photon336 · Answer

My understanding of reversible 
|dw:1444103353251:dw| 

Delta G has to do with like energy that's available to do work, I think that's where the "free comes from" would like to see someone derive it though.

anonymous · Answer

Wait this is multiple choice? I was thinking you were looking for the specific cases for each.

shikamaru11 · Answer

yeah Absolute rite @Photon336 Sir
and yep it's a multiple choice Ma dude @Woodward

photon336 · Answer

@Shikamaru11 you take organic yet?

shikamaru11 · Answer

nope I'm going with both @Photon336 Sir

photon336 · Answer

Well, i'm out guy take care, welcome to OS  shika!

shikamaru11 · Answer

it's yours gratitude you came Sir @Photon336  :) stay happy @Woodward both of you

shikamaru11 · Answer

@Rushwr Sir it's reversible