Why is entropy extensive?

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Emily Glaser 1F
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Joined: Thu Jul 27, 2017 2:01 am

Why is entropy extensive?

Postby Emily Glaser 1F » Mon Mar 12, 2018 2:02 pm

If q=mCT

and delta S = q/T, doesn't that involve mass (intensive)

Hannah Chew 2A
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Re: Why is entropy extensive?

Postby Hannah Chew 2A » Mon Mar 12, 2018 2:07 pm

An extensive property is dependent on size (or mass), and like you said, entropy = q/T, and q in itself is dependent on the mass, so therefore, it is extensive. Mass is an extensive property.

An example of an intensive property would be density of water. No matter how much water you have, the density still remains the same.

Ya Gao
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Re: Why is entropy extensive?

Postby Ya Gao » Mon Mar 12, 2018 2:49 pm

Entropy is a extensive property because it depends on the number of moles involved ( involves mass, size )

Kyle Alves 3K
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Joined: Thu Jul 27, 2017 2:01 am

Re: Why is entropy extensive?

Postby Kyle Alves 3K » Tue Mar 13, 2018 8:23 pm

The easy way to remember is:
an extensive property is energy/temperature, only depends on amount of substance (heat capacity is in kJ/K which is like q/T)
an intensive property is energy/(temperature x amount), which is like kJ/(C x g) for specific heat or J/(K x mol) for heat capacity

Michael Downs 1L
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Joined: Thu Jul 13, 2017 2:00 am

Re: Why is entropy extensive?

Postby Michael Downs 1L » Fri Mar 16, 2018 8:03 pm

This is very helpful

Rishi Khettry 1L
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Joined: Fri Sep 29, 2017 6:05 am

Re: Why is entropy extensive?

Postby Rishi Khettry 1L » Sat Mar 17, 2018 12:59 am

Extensive is dependent while intensive is independent


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