| Author |
Message
|
| LikimysCrotchus5 |
Posted: 05/16/2008 15:19 PM Post subject: |
|
|
 Brigadier General

Joined: 04 Sep 2007 Posts: 976 2288.98 Spud Bux
|
| BC Pneumatics wrote: | | Well, most of the credit goes to Clapeyron, but I'm glad I could help. |
So im guessing he is the one who made one of these laws?
I am actually surprised to see that i am learning this now in chemistry and it pops up again in the forum.
For anyone who is curious, you can manipulate this formula to solve for different variable but this is the basic equation i leanred.
PV = nRT where:
P = pressure (usually in kPa or atm)
V = volume (usually in Liters)
n = amount of gas (usually in moles)
R = ideal gas constant (8.31 kPa or 0.0821 in atm)
T = Temperature (usually in Kelvin)
So as long as you have all of these variable but one, you cant solve for the missing variable.
And if anyone needs to find the how much pressure, volume or temperature changes depending on what you change, you can use the combined gas formula which is:
P1*V1/T1 = P2*V2/T2 where:
P1 = pressure of first container (usually in kPa)
V1 = volume of first container (usually in Liters)
T1 = temperature of the gas (usually in Kelvin)
P2 = pressure of second container (kPa)
V2 = volume of second container (Liters)
T2 = temperature of second container (Kelvin)
And if one of those variables is missing, then you can solve for it by manipulating the equation.
This was my dollar and 2 cents.
|
|
| Back to top |
|
 |
|
|
 |
| BC Pneumatics |
Posted: 05/16/2008 17:16 PM Post subject: |
|
|
 Donating Moderator

Joined: 18 Jan 2005 Posts: 1142 2428.25 Spud Bux
|
Well Liki, he came up with 'PV=nRT', which is the base from which everything else you wrote is derived. There are also tons of forms you didn't mention, but they are not particularly helpful to us. They are mostly forms where things like 'n' (moles of gas) are substituted out and replaced with stuff like 'mass/molar mass' You can make tons of substitutions and get very complex, the only advantage of which is a better fit for your application.
He did other stuff too, but none of it is terribly relevant to us.
|
|
| Back to top |
|
 |
| LikimysCrotchus5 |
Posted: 05/16/2008 17:22 PM Post subject: |
|
|
 Brigadier General

Joined: 04 Sep 2007 Posts: 976 2288.98 Spud Bux
|
| BCPneumatics wrote: | | There are also tons of forms you didn't mention, but they are not particularly helpful to us. They are mostly forms where things like 'n' (moles of gas) are substituted out and replaced with stuff like 'mass/molar mass' |
Hence the reason i wrote usually
But really to make these suited for our needs, all one must do is convert from different measurements of pressure, volume, and temperature and then we can apply it to what we do.
|
|
| Back to top |
|
 |
| BC Pneumatics |
Posted: 05/16/2008 17:24 PM Post subject: |
|
|
 Donating Moderator

Joined: 18 Jan 2005 Posts: 1142 2428.25 Spud Bux
|
| It may also be noted that what I posted in this topic to begin with, is nothing more than PV=nRT, rearranged, and with some variables replaced with constants. Not to mention a bunch of unit conversions.
|
|
| Back to top |
|
 |
| LikimysCrotchus5 |
Posted: 05/16/2008 17:31 PM Post subject: |
|
|
 Brigadier General

Joined: 04 Sep 2007 Posts: 976 2288.98 Spud Bux
|
Too bad this ideal gas law wont be accurate in areas of in areas of high temperature, because ideal gasses cannot become solid or liquid, which is why they dont exist and are only used to predict.
But im sure you already know this.
|
|
| Back to top |
|
 |
| BC Pneumatics |
Posted: 05/16/2008 18:03 PM Post subject: |
|
|
 Donating Moderator

Joined: 18 Jan 2005 Posts: 1142 2428.25 Spud Bux
|
Liki, you are completely correct, the 'ideal gas' does not exist. That is why we must use V=((nRT)/P)+nb where 'n'= moles of gas and 'b'= a constant intrinsic to each gas to account for non ideal gas volume.
And corrected for intermolecular forces, it is P=((nRT)/V)-(a(n/V)^2)). Here 'a' is a constant intrinsic to each gas.
We of course owe a great deal of gratitude to Van der Waals for figuring these corrections, and combining them into the Van der Waals equation. (No one ever said he was humble.)
Equations are very jarbled in regular text, so I used an image to represent that equation in it's common form.
| Description: |
|
| Filesize: |
1.56 KB |
| Viewed: |
143 Time(s) |

|
Last edited by BC Pneumatics on 05/17/2008 12:50 PM; edited 1 time in total |
|
| Back to top |
|
 |
| LikimysCrotchus5 |
Posted: 05/16/2008 20:58 PM Post subject: |
|
|
 Brigadier General

Joined: 04 Sep 2007 Posts: 976 2288.98 Spud Bux
|
| BCPnuematics wrote: | That is why we must use V=((nRT)/P)+nb where 'n'= moles of gas and 'b'= a constant intrinsic to each gas to account for non ideal gas volume.
And corrected for intermolecular forces, it is P=((nRT)/V)-(a(n/V)^2)). Here 'a' is a constant intrinsic to each gas.
We of course owe a great deal of gratitude to Van der Waals for figuring these corrections, and combining them into the Van der Waals equation. (No one ever said he was humble.)
Equations are very jarbled in regular text, so I used an image to represent that equation in it's common form. |
Now i may not go into that with a chem 1 class, but i never knew that. So thats what you use here then, right?
My hats off to you sir
|
|
| Back to top |
|
 |
|
|