Chemistry
Solving for the amount of gas
The rearrangement used most often. Pressure and volume multiply on top; the gas constant and temperature divide below.
The Formula
n = P V / (R T)
The rearrangement used most often. Pressure and volume multiply on top; the gas constant and temperature divide below.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| n | Amount of gas in moles | moles | For 101.325 kPa, 22.4 L and 273.15 K this returns 0.9993767483 mol. |
| R | Gas constant in the units you are using | depends on the units chosen | 8.314462618 for kPa and litres, 0.08206 for atm and litres. |
What Each Symbol Means
nmoles
Amount of gas in moles
For 101.325 kPa, 22.4 L and 273.15 K this returns 0.9993767483 mol.
Rdepends on the units chosen
Gas constant in the units you are using
8.314462618 for kPa and litres, 0.08206 for atm and litres.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate the ideal gas law page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate The Ideal Gas Law, filed under Science. Every number the guide produces comes from substituting into this one line.