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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: kenhung123 on July 06, 2010, 01:29:18 am

Title: Assumption
Post by: kenhung123 on July 06, 2010, 01:29:18 am
When talking about physical change applied to a closed system at equilibrium do we assume the change is applied once only?
E.g. we increase the volume, the system would try to reduce the volume by shifting towards side with more particles but we won't then again increase it to maintain that particular volume right?
Title: Re: Assumption
Post by: Russ on July 06, 2010, 09:05:39 am
A change is generally only applied once, yes. Have you done the equilibrium graphs yet? Those are a pretty good representation of it and they helped me get it clear in my head.
Title: Re: Assumption
Post by: fady_22 on July 06, 2010, 11:30:53 am
When talking about physical change applied to a closed system at equilibrium do we assume the change is applied once only?
E.g. we increase the volume, the system would try to reduce the volume by shifting towards side with more particles but we won't then again increase it to maintain that particular volume right?

Yes you would assume that.
However, the system would not try to reduce the volume in this case (it can't really change the volume of the container). Rather, as the volume increases (for gases), the pressure in the container decreases. In order to increase the pressure, the reaction producing more particles is favoured, and so there is a net reaction in that direction.
Title: Re: Assumption
Post by: Stojad on July 06, 2010, 09:31:28 pm
When talking about physical change applied to a closed system at equilibrium do we assume the change is applied once only?
E.g. we increase the volume, the system would try to reduce the volume by shifting towards side with more particles but we won't then again increase it to maintain that particular volume right?

Yes you would assume that.
However, the system would not try to reduce the volume in this case (it can't really change the volume of the container). Rather, as the volume increases (for gases), the pressure in the container decreases. In order to increase the pressure, the reaction producing more particles is favoured, and so there is a net reaction in that direction.

Yes. Don't talk about it in terms of volume, but in terms of pressure.