Gas Constant

Moderators: Chem_Mod, Chem_Admin

Viviana Velasquez
Posts: 97
Joined: Sat Jul 20, 2019 12:15 am

Gas Constant

Postby Viviana Velasquez » Sun Jan 26, 2020 6:43 pm

Which gas constant are we expected to use for the equation PV=nRT?

Kimberly Koo 2I
Posts: 99
Joined: Sat Aug 17, 2019 12:17 am

Re: Gas Constant

Postby Kimberly Koo 2I » Sun Jan 26, 2020 6:46 pm

0.08206 L.atm.mol.K

TarynD_1I
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

Re: Gas Constant

Postby TarynD_1I » Sun Jan 26, 2020 6:49 pm

The gas constant depends on which measurement that the question uses (J, atm, bar, or torr usually) and it will be on the equations sheet.

Anna Chen 1K
Posts: 104
Joined: Thu Jul 25, 2019 12:18 am

Re: Gas Constant

Postby Anna Chen 1K » Sun Jan 26, 2020 9:57 pm

The value for the gas constant depends on the units used in the specific question.

Anna Heckler 2C
Posts: 102
Joined: Wed Sep 18, 2019 12:18 am

Re: Gas Constant

Postby Anna Heckler 2C » Sun Jan 26, 2020 9:59 pm

Use the gas constant that has the same units as the other values you are using in the calculation. For example, if your pressure is in atm, then use the gas constant that has the unit with atm (so they match and cancel).

105311039
Posts: 107
Joined: Fri Aug 02, 2019 12:16 am

Re: Gas Constant

Postby 105311039 » Sun Jan 26, 2020 10:05 pm

Every question can possibly be different, so you can necessarily pinpoint down one equation. It just depends on the question and units.

stephaniekim2K
Posts: 79
Joined: Fri Aug 09, 2019 12:16 am

Re: Gas Constant

Postby stephaniekim2K » Sun Jan 26, 2020 10:07 pm

There's a few different gas constants for different units but they are the same constant, just with different units. They are all on the formula sheet.

Charysa Santos 4G
Posts: 107
Joined: Wed Sep 18, 2019 12:21 am

Re: Gas Constant

Postby Charysa Santos 4G » Sun Jan 26, 2020 10:07 pm

The gas constant (R) depends on what other units are given to you when calculating PV = nRT. The units are included on the formula/equation sheet.

J_CHEN 4I
Posts: 54
Joined: Tue Nov 14, 2017 3:01 am

Re: Gas Constant

Postby J_CHEN 4I » Sun Jan 26, 2020 10:27 pm

Use the constant that includes the unit that is the same as the P in PV=nRT (so units cancel out nicely).

Sean Tran 2K
Posts: 65
Joined: Sat Aug 17, 2019 12:17 am

Re: Gas Constant

Postby Sean Tran 2K » Sun Jan 26, 2020 10:34 pm

The gas constant needed will be based on the units of pressure. The constants should be on the formula sheets during tests.

AronCainBayot2K
Posts: 101
Joined: Fri Aug 30, 2019 12:17 am

Re: Gas Constant

Postby AronCainBayot2K » Sun Jan 26, 2020 10:57 pm

The Gas Constant value is determined based on the pressure usually and other components in the ideal gas law equation. Pressure can be measured in atm, bar, etc, and R is represented in many of those units.

Jesse Anderson-Ramirez 3I
Posts: 54
Joined: Thu Sep 26, 2019 12:18 am

Re: Gas Constant

Postby Jesse Anderson-Ramirez 3I » Sun Jan 26, 2020 11:33 pm

The constants will be given on the formula sheet during the exams.

kausalya_1k
Posts: 50
Joined: Wed Nov 14, 2018 12:23 am

Re: Gas Constant

Postby kausalya_1k » Sun Jan 26, 2020 11:41 pm

It honestly depends what units P, V, and T are given. Typically we use .08206 L atm/mol K, but it really depends on units for the given values.

Astrid Lunde 1I
Posts: 103
Joined: Sat Sep 07, 2019 12:16 am

Re: Gas Constant

Postby Astrid Lunde 1I » Tue Jan 28, 2020 4:04 pm

The gas constant is given on the formula sheet, make sure you chose the one with the units that apply to the equation.


Return to “Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions”

Who is online

Users browsing this forum: No registered users and 1 guest