gas constants

[805939635]

There are quite a few ideal gas constants and my question is how do I know when to use each one. It seems like when there are atm involved we use 0.0821, but otherwise I find it hard to tell and that's more a patten than actual logic. Does anyone know when to use which? In high school I only ever used 8.314.

[Tiffany Wang 3L]

There are many different gas constants, 4 of which are given to us on the constants sheet. If you were to convert all the constants to the same units, it would just be one constant. The way to tell which one to use is to recognize the units of the values that are given to you, specifically the units of the pressure (bar, atm, Torr, etc.), so that you can cancel out the units to get your desired final answer.

[Ishika Gupta 3E]

There is only one gas constant, I think the different numbers you are finding are just the same constant in different units. To figure out which gas constant to use, find the units you are using and match them with the gas constant.

[Angela Ke]

To know which gas constant to use, just look at the units on the equation sheet. All the units should cancel out correctly. I think all the different values of R are found using dimensional analysis anyway.

[Kailyn Kennada 3E]

In all of your calculations the best thing you can do is simply look at what units you will need for the final answer you are solving for. If you need L or atm use 8.206 x10-2 whereas if you are going to need J use 8.134. Writing out all of the units and seeing what cancels out is important to deciding which gas constant to use. Hope this helps!

[Karina_Esqueda_2B]

The gas constant you need to use is based off the units you are given. There are several in order for them to correlate with the units you have been given.

[Rebecca Liu 2E]

I think the constants we need will be on the formulas and constants sheet from Professor Lavelle, we just have to make sure that we convert if needed so the units align and cancel out correctly.

[eriko vong 3D]

The gas constants are all the same, just in different units, so just be sure to pay extra attention to the units used in the problem to find out which one to use

[Camila Garcia 1F]

The gas constant you use depends on the original units given. For example, you would use 0.082057 when there are Liter units and 8.314472 when working with joules.