Using R

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Ariel Cheng 2I
Posts: 67
Joined: Fri Sep 28, 2018 12:29 am

Using R

Postby Ariel Cheng 2I » Sun Feb 10, 2019 7:57 pm

How do I know which R to use and when? Thanks.

Venya Vaddi 1L
Posts: 96
Joined: Fri Sep 28, 2018 12:16 am
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Re: Using R

Postby Venya Vaddi 1L » Sun Feb 10, 2019 7:59 pm

I usually check the units of the other terms in the equation to determine which value of R I need to use

Tessa Lawler 1A
Posts: 57
Joined: Fri Sep 28, 2018 12:18 am

Re: Using R

Postby Tessa Lawler 1A » Sun Feb 10, 2019 8:00 pm

Units! Check the units the given values are using.

Michelle Nwufo 2G
Posts: 61
Joined: Fri May 18, 2018 3:00 am

Re: Using R

Postby Michelle Nwufo 2G » Sun Feb 10, 2019 11:11 pm

Are we required to memorize all the different values of r?

Alma Flores 1D
Posts: 64
Joined: Wed Nov 08, 2017 3:01 am

Re: Using R

Postby Alma Flores 1D » Sun Feb 10, 2019 11:22 pm

All the different values for R should be on the constants and equations sheet provided.

jessicahe4Elavelle
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Re: Using R

Postby jessicahe4Elavelle » Mon Feb 11, 2019 12:01 am

All the values of R are in the equation sheet provided to us. To see which R to use, you should check the units, specifically if it uses atm or joules or Torr.

Rehan Chinoy 1K
Posts: 67
Joined: Fri Sep 28, 2018 12:25 am

Re: Using R

Postby Rehan Chinoy 1K » Mon Feb 11, 2019 2:38 pm

As stated above, on the midterm we will be provided with the formula sheet with the R gas constant in different forms due to different units. You just have to select the correct one based on the units of the given values.

105085381
Posts: 44
Joined: Fri Sep 28, 2018 12:15 am

Re: Using R

Postby 105085381 » Mon Feb 11, 2019 2:42 pm

So we know which form of R to use based off of the formula sheet provided to us? Can someone clairfy the possible unit values (atm or joules or Torr) per form of R?

Sarah Zhao 4C
Posts: 64
Joined: Fri Sep 28, 2018 12:28 am

Re: Using R

Postby Sarah Zhao 4C » Mon Feb 11, 2019 3:32 pm

We know which R to use based off what pressure unit is being used in the problem

PranitKumaran1F
Posts: 30
Joined: Thu Nov 08, 2018 12:17 am

Re: Using R

Postby PranitKumaran1F » Mon Feb 11, 2019 3:37 pm

R=8.314 J mol-1 K-1 is used more for solving for an energy value while R = .08206 L atm mol-1 K-1 is for when solving for either pressure or volume of a gas.

Shibhon_Shepard
Posts: 62
Joined: Wed Nov 15, 2017 3:04 am

Re: Using R

Postby Shibhon_Shepard » Wed Feb 20, 2019 1:30 pm

You usually use R=8.314 , but the other values for R are given on the equation sheet.


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