Celsius or Kelvin


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

Celsius or Kelvin

Postby Abigail Urbina 1K » Wed Jan 31, 2018 7:44 pm

If asked to calculate the changes in entropy and we are given temperature in terms of Celsius, do we always have to convert the temperature to be in terms of Kelvin? I know both can technically be considered correct, but is there a preferred method?

Kevin Ru 1D
Posts: 50
Joined: Thu Jul 13, 2017 3:00 am

Re: Celsius or Kelvin

Postby Kevin Ru 1D » Wed Jan 31, 2018 8:04 pm

You should convert to Kelvin as it is no longer ΔT in the equation, but T (The general formula for change in entropy being ΔS = qrev/T).

905022356
Posts: 48
Joined: Mon Oct 02, 2017 7:19 am

Re: Celsius or Kelvin

Postby 905022356 » Wed Jan 31, 2018 8:49 pm

When in doubt, it is always best to convert the temperature to Kelvin by adding 273.15.

Jason Liu 1C
Posts: 52
Joined: Fri Sep 29, 2017 7:04 am

Re: Celsius or Kelvin

Postby Jason Liu 1C » Wed Jan 31, 2018 8:51 pm

For problems with ΔT, you can use either Celsius or Kelvin because the difference between the temperatures will be the same. However, for problems with just T, you should generally use Kelvin because that is the SI unit.

Erica Nagase 1H
Posts: 30
Joined: Sat Jul 22, 2017 3:00 am

Re: Celsius or Kelvin

Postby Erica Nagase 1H » Thu Feb 01, 2018 10:15 am

For problems with ln, temperature has to be in K because the conversion factor is additive (+273) and won't cancel out. In comparison, the units don't really matter for problems with ln or ln because the conversion factors are multiplied (like x1000mL) and cancel out.

Cynthia Bui 2H
Posts: 30
Joined: Fri Sep 29, 2017 7:05 am

Re: Celsius or Kelvin

Postby Cynthia Bui 2H » Thu Feb 01, 2018 10:17 am

Definitely Kelvin.


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