Kelvin or Celsius?

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Veronica Lu 2H
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Kelvin or Celsius?

Postby Veronica Lu 2H » Sun Feb 09, 2020 10:03 pm

when using PV=nRT is the temperature supposed to be celsius or kelvin?

KSong_1J
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Re: Kelvin or Celsius?

Postby KSong_1J » Sun Feb 09, 2020 10:05 pm

I think you use Kelvin because the gas constant R always has Kelvin in the denominator so they cancel out!

Timmy Nguyen Dis 1I
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Re: Kelvin or Celsius?

Postby Timmy Nguyen Dis 1I » Sun Feb 09, 2020 11:01 pm

Use Kelvin

Shrayes Raman
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Re: Kelvin or Celsius?

Postby Shrayes Raman » Sun Feb 09, 2020 11:21 pm

Kelvin... The gas constant R is listed in Kelvin so Kelvin is used in equation.

Alexis Robles 2k
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Re: Kelvin or Celsius?

Postby Alexis Robles 2k » Sun Feb 09, 2020 11:58 pm

Whenever it is T alone, you should use kelvin but when it is deltaT, you can use Celcius or kelvin.

Venus_Hagan 2L
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Re: Kelvin or Celsius?

Postby Venus_Hagan 2L » Mon Feb 10, 2020 12:02 am

for the ideal gas equation use Kelvin but if you ever need the change in temperature it doesn't matter because both are scaled the same way

gconcha
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Re: Kelvin or Celsius?

Postby gconcha » Mon Feb 10, 2020 12:07 am

Kelvins are always used when applying the ideal gas law

The reason this is done is because Kelvins are more mathematically accurate in terms of chemically applying the excited state of the molecules in a gas to your calculations. zero K is the same as zero energy in the molecules, and is therefore the same as zero movement of the molecules. This is more mathematically correct than -273.15oC
If you really want, I'm sure you could look up values for the Ideal Gas Constant , but most are given in K because they're better for representing how the energy of the molecules affects the context.

Rosa Munoz 2E
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Re: Kelvin or Celsius?

Postby Rosa Munoz 2E » Sun Feb 16, 2020 9:10 pm

Kelvin. it only doesn't matter if we are talking about change. If it is a capital T then it must be Kelvin

Juana Abana 1G
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Re: Kelvin or Celsius?

Postby Juana Abana 1G » Tue Feb 18, 2020 9:13 pm

You would use kelvin.

Aarushi Solanki 4F
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Re: Kelvin or Celsius?

Postby Aarushi Solanki 4F » Tue Feb 18, 2020 9:20 pm

Kelvin, because the gas constant R is usually in terms of Kelvins.

205405339
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Re: Kelvin or Celsius?

Postby 205405339 » Tue Feb 18, 2020 9:36 pm

temperature is always kelvin

Jesse Anderson-Ramirez 3I
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Re: Kelvin or Celsius?

Postby Jesse Anderson-Ramirez 3I » Sun Feb 23, 2020 11:28 pm

Should use Kelvin so the units match the constant.

Anish Natarajan 4G
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Re: Kelvin or Celsius?

Postby Anish Natarajan 4G » Sun Mar 01, 2020 8:57 pm

Technically it's all dependent on the value of R that you use, but in most cases you'll be given a value that incorporates Kelvin rather than Celsius

Orrin Zhong 4G
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Re: Kelvin or Celsius?

Postby Orrin Zhong 4G » Sun Mar 01, 2020 8:58 pm

Temperature is always Kelvin in PV = nRT.

AronCainBayot2K
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Re: Kelvin or Celsius?

Postby AronCainBayot2K » Sun Mar 01, 2020 8:58 pm

Kelvin because the ideal gas constant is in terms of Kelvin not celsius.

CalvinTNguyen2D
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Re: Kelvin or Celsius?

Postby CalvinTNguyen2D » Sun Mar 01, 2020 9:28 pm

You will almost always be using Kelvin in equations and calculations; in terms of the gas constant, it is measured in Kelvin rather than Celsius.

Celine 1F
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Re: Kelvin or Celsius?

Postby Celine 1F » Sun Mar 01, 2020 9:32 pm

Definitely use Kelvin

105311039
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Re: Kelvin or Celsius?

Postby 105311039 » Sun Mar 01, 2020 9:38 pm

you must use Kelvin because of the units in the gas constant R

Sean Tran 2K
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Re: Kelvin or Celsius?

Postby Sean Tran 2K » Sun Mar 01, 2020 11:46 pm

Use Kelvin, as the gas constant R includes it.

605395381
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Re: Kelvin or Celsius?

Postby 605395381 » Mon Mar 02, 2020 8:03 am

kelvin, just make sure the units for R is the same

AveryAgosto
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Re: Kelvin or Celsius?

Postby AveryAgosto » Mon Mar 02, 2020 8:51 am

You should use Kelvin because R uses Kelvin.

Esha Chawla 2E
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Re: Kelvin or Celsius?

Postby Esha Chawla 2E » Mon Mar 02, 2020 9:07 am

Veronica Lu 2H wrote:when using PV=nRT is the temperature supposed to be celsius or kelvin?


The units for R are L*atm/mol*K. Based on this information, we can determine that R should be in Kelvin.

In general, most chemical reactions use temperature in Kelvin.

Aarushi Solanki 4F
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Re: Kelvin or Celsius?

Postby Aarushi Solanki 4F » Mon Mar 02, 2020 10:12 am

It's supposed to be in Kelvin. Generally, we use Kelvin, but it is okay to use Celsius in equations involving the "change of T" since the scaling is the same for Kelvin and Celsius.

Gurmukhi Bevli 4G
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Re: Kelvin or Celsius?

Postby Gurmukhi Bevli 4G » Sat Mar 07, 2020 12:20 am

The temperature should be in kelvin.

Brandi 2C
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Re: Kelvin or Celsius?

Postby Brandi 2C » Sat Mar 07, 2020 12:26 am

Since the STP (standard temperature and pressure) and R constant are in units of Kelvin, you should be using Kelvin for your calculations. If the problem does ask for the answer in units of Celsius, just do the calculations in Kelvin and then convert to Celsius after completing the calculations so you don't mess up unit calculations.

Madeline Phan 1E
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Re: Kelvin or Celsius?

Postby Madeline Phan 1E » Sat Mar 07, 2020 11:01 am

You use Kelvin since the units of R include Kelvin.

Yailin Romo 4G
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Re: Kelvin or Celsius?

Postby Yailin Romo 4G » Sat Mar 07, 2020 10:42 pm

Temperature is always in Kelvin, not Celsius.

Owen-Koetters-4I
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Re: Kelvin or Celsius?

Postby Owen-Koetters-4I » Sun Mar 08, 2020 6:40 pm

kelvin

Areli C 1L
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Re: Kelvin or Celsius?

Postby Areli C 1L » Sun Mar 08, 2020 10:02 pm

yup, as mentioned above, you would use Kelvin.

Justin Quan 4I
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Re: Kelvin or Celsius?

Postby Justin Quan 4I » Mon Mar 09, 2020 1:50 pm

Veronica Lu 2H wrote:when using PV=nRT is the temperature supposed to be celsius or kelvin?

To add on, you use kelvin especially since the constant R is in kelvin, not celsius. However, if you use PV=nR∆T, the you may use either celsius or kelvin since the change in temperature would be the same.

Alfred Barrion 2H
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Re: Kelvin or Celsius?

Postby Alfred Barrion 2H » Mon Mar 09, 2020 1:54 pm

You should use Kelvin since it matches with the gas constant R to cancel out.

105335337
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Re: Kelvin or Celsius?

Postby 105335337 » Mon Mar 09, 2020 2:10 pm

You use Kelvin because you must match the units within the R (gas constant) which uses kelvin.

pmokh14B
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Re: Kelvin or Celsius?

Postby pmokh14B » Mon Mar 09, 2020 2:18 pm

kelvin because the gas constant is always in terms of kelvin.

William Chan 1D
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Re: Kelvin or Celsius?

Postby William Chan 1D » Wed Mar 11, 2020 10:24 pm

Kelvin. If the reaction happened at below 0°C, then the subsequent equation would be negative, having some weird consequences (i.e., negative pressure, negative volume).

Bryan Chen 1H
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Re: Kelvin or Celsius?

Postby Bryan Chen 1H » Wed Mar 11, 2020 10:25 pm

it depends on the unit of the gas constant. if its .08206 Latm/Kmol then use Kelvin, but another gas constant COULD have its units in celcius for whatever reason and then you should use celcius (but it probably will never ever come up in real life or a problem)

Leonardo Le Merle 1D
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Re: Kelvin or Celsius?

Postby Leonardo Le Merle 1D » Thu Mar 12, 2020 11:06 am

Kelvin = Celsius + 273.15; the two are on the same scale so converting between the two isn't too tricky.

Tanmay Singhal 1H
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Re: Kelvin or Celsius?

Postby Tanmay Singhal 1H » Thu Mar 12, 2020 11:07 am

kelvin because the gas constant R is in K. sometimes it is in C and in that case u would use C

Kavya Immadisetty 2B
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Re: Kelvin or Celsius?

Postby Kavya Immadisetty 2B » Thu Mar 12, 2020 11:23 am

Kelvin, just make sure all the units cancel

Rodrigo2J
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Re: Kelvin or Celsius?

Postby Rodrigo2J » Thu Mar 12, 2020 11:45 am

Kelvin

Alan Cornejo 1a
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Re: Kelvin or Celsius?

Postby Alan Cornejo 1a » Sun Mar 15, 2020 8:06 am

Use kelvin and make sure your units match up.

Elizabeth Harty 1A
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Re: Kelvin or Celsius?

Postby Elizabeth Harty 1A » Sun Mar 15, 2020 12:50 pm

Kelvin

Anushka Chauhan2B
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Re: Kelvin or Celsius?

Postby Anushka Chauhan2B » Sun Mar 15, 2020 1:22 pm

kelvin

Ayushi2011
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Re: Kelvin or Celsius?

Postby Ayushi2011 » Mon Mar 16, 2020 6:10 pm

Kelvin is always the unit for such equations.

Charlene Datu 2E
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Re: Kelvin or Celsius?

Postby Charlene Datu 2E » Mon Mar 16, 2020 7:12 pm

It's always in Kelvin because the R constant uses units of Kelvin

BAlvarado_1L
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Re: Kelvin or Celsius?

Postby BAlvarado_1L » Tue Mar 17, 2020 12:27 pm

kelvin so it cancels out with the units of R

SVajragiri_1C
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Re: Kelvin or Celsius?

Postby SVajragiri_1C » Tue Mar 17, 2020 8:42 pm

You use Kelvin, because the unit for R in this equation has K in it.

EllieSchmidtke_4I
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Re: Kelvin or Celsius?

Postby EllieSchmidtke_4I » Tue Mar 17, 2020 9:31 pm

Use Kelvin since this is the SI unit for temperature.

Bella Townsend
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Re: Kelvin or Celsius?

Postby Bella Townsend » Tue Mar 17, 2020 10:19 pm

Typically, you only ever use celsius is there is a change in temperature (delta T) because then the units don't matter. The difference will be the same.


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