Ideal Gas Law

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Ideal Gas Law is a gas law that represents pressure, volume and temperature relationships with the number of moles of gas. The Ideal Gas Law can written as PV=nRT In the Ideal Gas Law "n" is the amount of moles gas present, "R" is the ideal gas constant an it is represented by the value 0.08205784 L.atm/mol . K, "P" is pressure in atm, "V" is volume in Liters and "T" is temperature measured in Kelvin "K".The formula for Kelvin is K= C + 273.15.

Example Problem:

What pressure measured in atmospheres "atm"  is exerted by .500mol of nitrogen gas in a 2.0 L gas container at 285 K?

n= .500 mol

R= 0.08205784 L.atm/ mol .K

T= 285 K

P= ?

V= 2.0 L

You take the Ideal Gas Law  PV=nRT and rearrange the variables to fit the new formula for the variable that needs to be solved.

P= nRT/ V

_{P= .500 moL (0.08205784 L .atm / moL. K) (285 K) / 2.0 L}

P= _{5.85 atm}