Question regarding entropy

[Deng13]

Since the second law of thermodynamics states that all spontaneous reactions increase in entropy....but cant a spontaneous reaction have a decrease in entropy???

For example:

G = H - TS

What if S is negative, and H is negative....couldnt G be negative at really low temperatures???

Doesnt that mean not all spontaneous reactions have to have an increase in entropy??

It was in DAT destroyer too...Question 33 2008 edition. Sorry its really annoying me cause i dont know what is the correct way to look at in if a quesiton does show up on the test.

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[Avery07]

Since the second law of thermodynamics states that all spontaneous reactions increase in entropy....but cant a spontaneous reaction have a decrease in entropy???

For example:

G = H - TS

What if S is negative, and H is negative....couldnt G be negative at really low temperatures???

Doesnt that mean not all spontaneous reactions have to have an increase in entropy??

It was in DAT destroyer too...Question 33 2008 edition. Sorry its really annoying me cause i dont know what is the correct way to look at in if a quesiton does show up on the test.

Are you confusing deltaG (gibbs free energy) with deltaS (change in entropy)?

 

[Deng13]

Are you confusing deltaG (gibbs free energy) with deltaS (change in entropy)?

No I am wondering isnt it possible to have a spontaneous reaction with a decrease it entropy? Why does it always have to be an increase in entropy.

My chem book gives an example where they you are going from water to ice. Which is a decrease in entropy...at really low temperatures which also happens to be an exothermic reaction. That reaction is spontaneous and has a decrease in entropy. Doesnt that prove the second law false?

 

[Avery07]

No I am wondering isnt it possible to have a spontaneous reaction with a decrease it entropy? Why does it always have to be an increase in entropy.

My chem book gives an example where they you are going from water to ice. Which is a decrease in entropy...at really low temperatures which also happens to be an exothermic reaction. That reaction is spontaneous and has a decrease in entropy. Doesnt that prove the second law false?

The system can decrease in entropy but the system + surroundings (universe) will always increase in entropy.

 

[Deng13]

The system can decrease in entropy but the system + surroundings (universe) will always increase in entropy.

OHHHH lol hahaha dang good call dude. wow i feel stupid. thanks a lot man.