Physics
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Ideal Gas Law Calculator.
Solve one missing pressure, volume, amount, or temperature value with PV = nRT.
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Kelvin only; convert Celsius before entering
Results update automatically. Leave exactly one value blank.
Calculated value: Temperature
Using PV = nRT and R = 8.314462618 J/(mol·K), the missing value is isolated from the other three SI inputs.
Gas constant used: R = 8.31446261815324 J/(mol·K).
How to Use
Ideal-gas law: P × V = n × R × T, where R = 8.314462618 J/(mol·K).
Use SI units: pressure in pascals (Pa), volume in cubic metres (m³), amount in moles (mol), and absolute temperature in kelvin (K).
This is an ideal-gas model. Real gases can differ, especially at high pressure or near condensation.
FAQs
What is the ideal gas law?
The ideal gas law is PV = nRT, where P is pressure, V is volume, n is amount of gas, R is the gas constant, and T is absolute temperature.
Which units should I enter?
Use pascals, cubic metres, moles, and kelvin. Convert Celsius to kelvin before entering temperature.
Do real gases always follow this equation?
No. The result is an ideal-gas approximation and can differ for real gases at high pressure or near condensation.