Volume of Gas Calculator
Calculate the volume of a gas from moles, pressure, and temperature using V = nRT/P.
Related Calculators
Ideal Gas Law
Combined Gas Law
Charles's Law
Boyle's Law
Gay-Lussac's Law
Dalton's Law
Avogadro's Law
Volume of Gas Formula
The volume of a gas is calculated from the ideal gas law, rearranged to solve for V:
Volume at STP (Molar Volume Table)
At Standard Temperature and Pressure (0°C = 273.15 K, 1 atm), every mole of ideal gas occupies 22.4 L:
| Moles (n) | Volume at STP (L) |
|---|---|
| 0.25 | 5.6 |
| 0.5 | 11.2 |
| 1.0 | 22.4 |
| 2.0 | 44.8 |
| 3.0 | 67.2 |
| 5.0 | 112.0 |
| 10.0 | 224.0 |
Moles to atm Conversion
"Moles to atm" is not a direct conversion since they measure different things (amount vs pressure). However, using PV = nRT, if you know n, V, and T, you can find P:
For example: 2.0 mol of gas in 10.0 L at 300 K: P = (2.0)(0.08206)(300) / 10.0 = 4.924 atm.
Step-by-Step Examples
Example 1: Volume at STP
Given: n = 3.5 mol at STP (1 atm, 273.15 K). Find V.
Example 2: Volume at Non-Standard Conditions
Given: n = 1.0 mol, P = 2.0 atm, T = 400 K. Find V.
For a full PV=nRT calculator that can solve for any variable, see the Ideal Gas Law Calculator.
Frequently Asked Questions
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Use the formula V = nRT/P from the ideal gas law. You need the number of moles (n), the gas constant (R), the temperature in Kelvin (T), and the pressure (P). At STP (1 atm, 273.15 K), you can simply multiply moles by 22.4 L/mol.
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At Standard Temperature and Pressure (0°C and 1 atm), one mole of any ideal gas occupies 22.4 liters. This is called the molar volume.
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Moles and atm are different quantities (amount vs pressure), so you cannot directly convert between them. However, using PV = nRT, if you know moles (n), volume (V), and temperature (T), you can calculate pressure: P = nRT/V.