Combined Gas Law Calculator
💨 Gas Laws & Fluids. Use the Combined gas law formula to find pressure 1, volume 1, temperature 1, pressure 2, volume 2, temperature 2: pick the value you want, type the others, and the answer updates as you go.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Pressure 1 | kPa |
| Volume 1 | L |
| Temperature 1 | K |
| Pressure 2 | kPa |
| Volume 2 | L |
| Temperature 2 | K |
Worked example
Find the pressure 1 when Volume 1 = 2 L, Temperature 1 = 300 K, Pressure 2 = 150 kPa, Volume 2 = 1.6 L, Temperature 2 = 360 K.
Using (P1 V1)/T1 = (P2 V2)/T2: Pressure 1 = 100 kPa.
Frequently asked questions
What is the formula for Combined gas law?
(P1 V1)/T1 = (P2 V2)/T2.
What do the letters stand for, and what units are used?
Pressure 1 in kPa, Volume 1 in L, Temperature 1 in K, Pressure 2 in kPa, Volume 2 in L, Temperature 2 in K.
How do you calculate pressure 1?
Put the values into (P1 V1)/T1 = (P2 V2)/T2. For example, with Volume 1 = 2 L, Temperature 1 = 300 K, Pressure 2 = 150 kPa, Volume 2 = 1.6 L, Temperature 2 = 360 K, pressure 1 = 100 kPa.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (pressure 1, volume 1, temperature 1, pressure 2, volume 2, temperature 2) and fill in the others: it rearranges the formula for you.
