Calculate gas pressure or volume from the ideal gas law using temperature, moles, and common units for volume and pressure in liters, atm, and Pa.
Pressure Formula
The following formula is used to calculate the Pressure.
P = nrt / V
- Where P is the Pressure (Pa)
- V is the total volume (m^3)
- n is the amount of substance (moles)
- T is the temperature (K)
- r is the universal gas constant (8.3144626 J/k-mol)
| Atmospheres (atm) | Kilopascals (kPa) | Bar (bar) | Pounds per square inch (psi) | Pascals (Pa) |
|---|---|---|---|---|
| 0.1 | 10.133 | 0.10133 | 1.47 | 10132.5 |
| 0.2 | 20.265 | 0.20265 | 2.94 | 20265.0 |
| 0.3 | 30.398 | 0.30398 | 4.41 | 30397.5 |
| 0.4 | 40.530 | 0.40530 | 5.88 | 40530.0 |
| 0.5 | 50.663 | 0.50663 | 7.35 | 50662.5 |
| 0.6 | 60.795 | 0.60795 | 8.82 | 60795.0 |
| 0.7 | 70.928 | 0.70928 | 10.29 | 70927.5 |
| 0.8 | 81.060 | 0.81060 | 11.76 | 81060.0 |
| 0.9 | 91.193 | 0.91193 | 13.23 | 91192.5 |
| 1.0 | 101.325 | 1.01325 | 14.70 | 101325.0 |
| 1.1 | 111.458 | 1.11458 | 16.17 | 111457.5 |
| 1.2 | 121.590 | 1.21590 | 17.64 | 121590.0 |
| 1.3 | 131.723 | 1.31723 | 19.10 | 131722.5 |
| 1.4 | 141.855 | 1.41855 | 20.57 | 141855.0 |
| 1.5 | 151.988 | 1.51988 | 22.04 | 151987.5 |
| 1.6 | 162.120 | 1.62120 | 23.51 | 162120.0 |
| 1.7 | 172.253 | 1.72253 | 24.98 | 172252.5 |
| 1.8 | 182.385 | 1.82385 | 26.45 | 182385.0 |
| 1.9 | 192.518 | 1.92518 | 27.92 | 192517.5 |
| 2.0 | 202.650 | 2.02650 | 29.39 | 202650.0 |
| Exact factors used: 1 atm = 101325 Pa = 101.325 kPa ≈ 1.01325 bar ≈ 14.6959 psi. | ||||
How to Calculate Pressure?
The following example problems outline how to calculate the Pressure.
Example Problem #1
- First, determine the total volume (m^3). In this example, the total volume (m^3) is given as 50 .
- Next, determine the amount of substance (moles). For this problem, the amount of substance (moles) is given as 10 .
- Next, determine the temperature (K). In this case, the temperature (K) is found to be 50.
- Finally, calculate the Pressure using the formula above:
P = nrt / V
Inserting the values from above and solving yields:
P = 50*8.314*10 / 50 = 83.14 (Pa)
Example Problem #2
Using the same method as above, determine the variables required by the equation. For this example problem, these are provided as:
total volume (m^3) = 501
amount of substance (moles) = 59
temperature (K) = 19
Enter these given values yields:
P = 59*8.3144*19 / 501 = 18.603 (Pa)
