units conversion for entropy


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Hannah Krusenoski 2L
Posts: 31
Joined: Fri Sep 29, 2017 7:06 am

units conversion for entropy

Postby Hannah Krusenoski 2L » Thu Feb 01, 2018 4:12 pm

Does it matter whether the units for entropy are in J/K or kj/K?

Melodie Oh 2A
Posts: 22
Joined: Fri Sep 29, 2017 7:06 am

Re: units conversion for entropy

Postby Melodie Oh 2A » Thu Feb 01, 2018 5:09 pm

It doesn't really matter but usually entropy is in J/K due to the equation of S=q/T

Harrison Wang 1H
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

Re: units conversion for entropy

Postby Harrison Wang 1H » Thu Feb 01, 2018 6:55 pm

The only case where this would matter would be in a problem and some values are in j/k and kj/k. Here, you would convert all units to either j/k or kj/k.

Sarah Rutzick 1L
Posts: 50
Joined: Tue Oct 10, 2017 7:13 am

Re: units conversion for entropy

Postby Sarah Rutzick 1L » Thu Feb 01, 2018 6:55 pm

It doesn't matter what unit you use as long as you use the same unit for any other steps in the problem

Helen Shi 1J
Posts: 78
Joined: Sat Jul 22, 2017 3:00 am

Re: units conversion for entropy

Postby Helen Shi 1J » Sat Feb 10, 2018 4:44 pm

I understand that the units for entropy is J/K, but can someone explain the reasoning behind it other than that it comes from the equation: delta S= q/T?

Scott Chin_1E
Posts: 55
Joined: Sat Jul 22, 2017 3:00 am

Re: units conversion for entropy

Postby Scott Chin_1E » Sat Feb 10, 2018 4:49 pm

I think temperature is usually expressed in Kelvin as most of the conversions and constants are also expressed in Kelvin, so it makes it easier for calculations and as for Joules versus Kilojoules, q is usually found using heat capacity which is expressed in Joules.

Abigail Urbina 1K
Posts: 102
Joined: Thu Jul 27, 2017 3:01 am

Re: units conversion for entropy

Postby Abigail Urbina 1K » Sat Feb 10, 2018 5:27 pm

Usually, the units for entropy are J/K. However, it shouldn't really matter. One thing to be mindful of, though, is keeping your units consistent throughout your calculations. Let's say you are adding up different values for entropies. You want to make sure you are adding entropies that all have units of J/K (or kJ/K, should you decide to calculate using those units).


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