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Charles Law calculator
Charles Law calculatorCharles' Law
V₁/T₁ = V₂/T₂ · Isobaric Gas Behavior Engine
Charles' Law requires absolute temperature (Kelvin). Celsius/Fahrenheit inputs are auto-converted.
About the Charles Law calculator
Charles's law says that at constant pressure the volume of a gas is proportional to its absolute temperature. Solve for any unknown volume or temperature.
How to use the Charles Law calculator
- Pick what to find under Solve For Unknown: V₁, T₁, V₂ or T₂.
- Enter the known values and choose the Temperature Unit (Kelvin is recommended).
- Press Calculate.
Formula and method
V₁ ÷ T₁ = V₂ ÷ T₂, with temperatures in kelvin. K = °C + 273.15.
Worked example
3.0 L of gas at 300 K heated to 600 K (at constant pressure) expands to 3.0 × 600 ÷ 300 = 6.0 L.
Tips
- Always convert Celsius or Fahrenheit to kelvin before calculating by hand.
- The law assumes constant pressure and amount of gas.
Frequently Asked Questions
Kelvin starts at absolute zero, so temperature is proportional to volume. Celsius does not start at zero, which would give wrong ratios.