1. The Ideal Gas Law PV=nRT P = Pressure V = Volume n = Number of Moles
R = ideal gas constant
T = temperature in Kelvin

3. R -The ideal gas constant
Depends on unit of pressure
L . Atm / K . mol
62.4 L . mmHg / K . mol (torr is mm Hg)
8.31 L . kPa / K . mol

4. Ideal Gas Law example problem
Calculate the pressure of 1.65 g of helium gas at 16.0oC and occupying a volume of 3.25 L?
You will need g to moles and Celsius to Kelvin:
1.65 g He 1 mole He
4.0 g He = mol He
K = oC ; = 289 K
For this problem you will need to pick an R value. For this problem I will choose to use the R value containing kPa. I picked it. You can’t do anything about it. So; just try and stop me.
Plug and Chug baby, get ‘R done. Do it. Come on I dare ya.
Get it - ‘R as in ideal gas constant

5. Ideal Gas Law example problem
P x 3.25 L = mol x 8.31 kPa . L x 289 K
mol . K
Do the algebra and solve; if you do it right, guess what? You get the answer right. Neat concept, huh? Maybe your mommy will give you a cookie.
= 305 kPa
Your turn
How many moles of gas are present in a sample of Argon at 58oC with a volume of 275 mL and a pressure of atm.

6. Ideal Gas Law example problem
Answer
0.987 atm x L = n x L . Atm x 331K
mol . K
Do the dew; oops, I mean the algebra and presto; the answer with the correct number of sig figs is..
Do you know how to keep a so called chem student in suspense?
Do ya?
= mol Ar
Congrats - you can plug and chug.
Bye Bye now.