Spontaneous Reactions: Forward, Backwards, Both or None?

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higherme
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Homework Statement



Find whether the following is spontaneous. Forward= (process as written), backwards, both or none

Homework Equations


1. water & syrup mixed to give a flavoured drink
2. Piece of paer at room temp react with O2 to give CO2 and H2O
3. Bathtub water gets cold after you stay in too long
4. Water freezes at 10C & 1 atm

The Attempt at a Solution


1. backwards b/c you have to stir it for water and syrup to mix
2. none? I'm not sure about this one. I don't think paper can react to give water.
3. Forward
4. backwards - water doesn't freeze at 10C

Can someone double check this for me, thanks in advance!
 
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higherme said:
1. backwards b/c you have to stir it for water and syrup to mix

Not necesarilly - mixing goes on its own, albeit very slowly.

2. none? I'm not sure about this one. I don't think paper can react to give water.

Every compound containing carbon and hydrogen gives CO2 and H2O when it burns. Check what is paper made of. Again, oxidation without burning is a very slow process, but it goes on its own.

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methods
 
higherme said:

Homework Statement



Find whether the following is spontaneous. Forward= (process as written), backwards, both or none

Homework Equations


1. water & syrup mixed to give a flavoured drink
2. Piece of paer at room temp react with O2 to give CO2 and H2O
3. Bathtub water gets cold after you stay in too long
4. Water freezes at 10C & 1 atm

The Attempt at a Solution


1. backwards b/c you have to stir it for water and syrup to mix
This is so easy an English major could answer it. Your question stated, "1. water & syrup mixed...". emphasis mine.


The rest look OK.