Combined Gas Law Calculator
New volume of a fixed amount of gas after a change of pressure and temperature, with the ratio and the moles present.
Results
Volume
12.39480
L
Pressure
110.5988
kPa
Ratio
0.55299
Amount of substance
1.00000
mol
What this tool does
Boyle's, Charles's and Gay-Lussac's laws are all this one equation with a different quantity held still. Temperature has to be absolute: using Celsius gives wrong answers, and a gas at 0 °C is at 273.15 K, not at nothing. The default is one mole at standard conditions.
Formula
P₁V₁ ÷ T₁ = P₂V₂ ÷ T₂ (absolute temperatures)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
p1 | Pressure | kPa |
v1 | Volume | L |
t1 | Temperature | °C |
p2 | Pressure | kPa |
t2 | Temperature | °C |
V2 | Volume | L |
P2 | Pressure | kPa |
RA | Ratio | — |
NM | Amount of substance | mol |
Worked example
- Pressure101.325 kPa
- Volume22.414 L
- Temperature0 °C
- Pressure200 kPa
- Temperature25 °C
- Volume12.39480 L
- Pressure110.5988 kPa
- Ratio0.55299
- Amount of substance1.00000 mol
Limitations
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
- Temperatures below absolute zero (−273.15 °C) do not exist physically. The converter will still show the arithmetic result.
- Mixing units is the most common source of error. Convert every input to the units shown next to each field before calculating.