Equilibrium in a closed pop bottle

[pinkyjoshi65]

Why is a sealed pop bottle said to be in a state of equilibrium, while an opened bottle is not?

 

[ozymandias]

This is a bit of a semantic problem.

Thermodynamically, a system can only be in equilibrium with another system (this is, in fact, used to define temperature, the basic variable in thermodynamics).
Mechanically, a system is in equilibrium if the function that describes it does not change with time.
There is also chemical equilibrium and a host of other interpretations - I'm sure other disciplines have their own definitions of "equilibrium" as well. I'm not sure which meaning your usage carries, so I can't really give you a full answer.

My guess is that by "equilibrium" the statement refers to "stationary", i.e., a system whose variables do not change in time appreciably. If that is the case, the closed bottle's properties (temperature, e.g.) are much less affected by the external surroundings compared to the open bottle and are therefore "constant to a degree".

--------
Assaf
http://www.physicallyincorrect.com/"

 

[chemisttree]

Do you observe any changes to the contents of a closed pop bottle? How about the contents of an open one?

 

[chemisttree]

This is a bit of a semantic problem.

Thermodynamically, a system can only be in equilibrium with another system (this is, in fact, used to define temperature, the basic variable in thermodynamics).
Mechanically, a system is in equilibrium if the function that describes it does not change with time.
There is also chemical equilibrium and a host of other interpretations - I'm sure other disciplines have their own definitions of "equilibrium" as well. I'm not sure which meaning your usage carries, so I can't really give you a full answer.

I think pinky's question refers to the equilibrium of dissolved CO2 in the system.

 

[ozymandias]

Arrrgh, after typing so much .

--------
Assaf
http://www.physicallyincorrect.com/"

 

[pinkyjoshi65]

um..so in a sealed pop bottle, what happens to the dissolved co2? it definitely stays in..any idea?

 

[Gokul43201]

What grade/level is this at?

What do you know about Henry's Law?

 

[pinkyjoshi65]

this is a grade 12 question. I have not studied about Henry's Law..This has to do with the elements inside the bottle I am guessing. If a closed bottle is at equi, then the components keep on forming again and again.

 

[chemisttree]

Describe what happens when you open a bottle of pop. BTW, we call that 'soda' down here in Texas.

 

[pinkyjoshi65]

when a soda bottle is opened, Co2 rushes out..

 

[chemisttree]

when a soda bottle is opened, Co2 rushes out..

After the initial pressure is released, what happens? Does this seem like it is in equilibrium?