Combined Gas Law Calculator
P₁V₁/T₁ = P₂V₂/T₂, with kelvin handled for you.
Work out Combined Gas Law. P₁V₁/T₁ = P₂V₂/T₂, with kelvin handled for you. Names the convention that makes the answer wrong.
Final volume (L)
1
2 L → 1 L
P₁V₁/T₁ = P₂V₂/T₂. Boyle, Charles and Gay-Lussac are all this equation with one variable held constant, which is why learning three laws is unnecessary. Temperatures convert to kelvin before anything else happens, because the relationship is proportional to absolute temperature.
How the Combined Gas Law Calculator works
Boyle, Charles and Gay-Lussac are all this one equation with a variable held constant, which is why learning three laws is unnecessary. Temperatures convert to kelvin before anything else happens, because the relationship is proportional to absolute temperature.
Also known as: p1v1t1 p2v2t2 calculator · gas law calculator · combined gas law formula · how to use the combined gas law
Frequently asked questions
What is the combined gas law?
P₁V₁/T₁ = P₂V₂/T₂. It relates a fixed amount of gas between two states, and reduces to Boyle, Charles or Gay-Lussac when one variable is held constant.
Why must temperature be in kelvin?
Because the relationship is proportional to absolute temperature. Using Celsius makes 0° into zero, implying a gas has no volume at freezing point, and the error looks plausible rather than obvious.
What is the difference from the ideal gas law?
The combined law compares two states of the same gas sample and needs no gas constant. The ideal gas law, PV = nRT, describes one state and requires the amount in moles.
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