Intensive vs. Extensive Properties

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Abigail Urbina 1K
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Joined: Thu Jul 27, 2017 3:01 am

Intensive vs. Extensive Properties

Postby Abigail Urbina 1K » Sun Jan 21, 2018 7:28 pm

I'm having a little bit of trouble distinguishing the differences between intensive and extensive properties. We were told that extensive properties are dependent on the amount of a substance, so one could imply that intensive properties would be the opposite. However, how are intensive properties not dependent on the amount of a substance? After all, specific heat for example, takes the mass of a substance into account. I've read several posts on here about it, and it seems like some of the posts contradict one another. Could someone explain the explicit differences with examples?

Gurshaan Nagra 2F
Posts: 49
Joined: Thu Jul 27, 2017 3:01 am

Re: Intensive vs. Extensive Properties

Postby Gurshaan Nagra 2F » Sun Jan 21, 2018 7:36 pm

Specific heat does not depend on the amount of substance, it only takes the mass into account in order to see how the temperature of the substance is affected. The definition of specific heat capacity is the amount of heat required to raise temp of 1 gram of a substance 1 degree celsius. I hope this helps with the discrepancies.

Nora Sharp 1C
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Joined: Sat Jul 22, 2017 3:00 am

Re: Intensive vs. Extensive Properties

Postby Nora Sharp 1C » Sun Jan 21, 2018 7:52 pm

I guess you could discern intensive and extensive properties by imagining a block of the substance you're examining, and then cutting it in half. If the characteristic you're trying to figure out is intensive or extensive changes, then it's extensive.

If I had a block of water and (hypothetically) I chopped it in half, both smaller pieces would still require 4.18 joules to heat up by 1 degree celcius for every gram, so specific heat capacity is an intensive property.

But if I had a 40g block of water with heat capacity 167.2J/K and chopped it in half, the two halves would no longer have the same heat capacity, because each one would require less energy to heat. The specific heat capacity would stay the same for the newer, smaller blocks of water, but the heat capacity would change.

Mitch Mologne 1A
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Joined: Fri Sep 29, 2017 7:04 am

Re: Intensive vs. Extensive Properties

Postby Mitch Mologne 1A » Sun Jan 21, 2018 8:17 pm

Put more simply, the specific heat of water will be the same in a 1g sample and a 1000g sample. Essentially, the property does not differ due to the amount of sample present.

Mitch Mologne 1A
Posts: 74
Joined: Fri Sep 29, 2017 7:04 am

Re: Intensive vs. Extensive Properties

Postby Mitch Mologne 1A » Sun Jan 21, 2018 8:17 pm

Put more simply, the specific heat of water will be the same in a 1g sample and a 1000g sample. Essentially, the property does not differ due to the amount of sample present.


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