Description
Return PV/(nRT) and its deviation from the ideal-gas value using caller-supplied consistent units and gas constant.
Thermal calculations distinguish absolute temperature from temperature change, and heat capacity from specific heat. An ideal-gas or expansion term also assumes a compatible unit system and a stated process or material model. Temperature-dependent properties, constraints, and real-gas effects can require a broader treatment.
Return PV/(nRT) and its deviation from the ideal-gas value using caller-supplied consistent units and gas constant.
When to use this tool
Use Idealgas Compressibility Residual One State when you need this expansion, heat-capacity, or ideal-gas term under the stated material and process assumptions.
How to use the tool and how it works
- Enter pressure, volume, moles, temperature, gasConstant. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read compressibility, residual. Use the output convention below.
For positive pressure, volume, moles, temperature, and gasConstant return compressibility=pressure*volume/(moles*gasConstant*temperature) and residual=compressibility-1.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| pressure | Pressure | Required. Finite number; strictly above 0. |
| volume | Volume in a unit compatible with the other physical inputs. | Required. Finite number; strictly above 0. |
| moles | Amount of substance in moles. | Required. Finite number; strictly above 0. |
| temperature | Positive absolute temperature in kelvin. | Required. Finite number; strictly above 0. |
| gasConstant | Gas constant in the chosen energy unit per mole per kelvin. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| compressibility | Dimensionless Z=PV/(nRT). | Required. Finite number. |
| residual | Signed observed-minus-implied discrepancy under the stated formula. | Required. Finite number. |
{
"input": {
"pressure": 2,
"volume": 3,
"moles": 1,
"temperature": 2,
"gasConstant": 3
},
"output": {
"compressibility": 1,
"residual": 0
}
}Limitations and assumptions
- Temperature is absolute kelvin and the gas constant must match the pressure-volume energy unit per mole per kelvin. A deviation is reported without fitting a real-gas equation or assessing measurement quality.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Use temperature-dependent properties or an appropriate equation of state when the ideal approximation is inadequate. Keep pressure-volume units compatible with the chosen gas constant and distinguish kelvin from temperature differences.
References
Similar or alternative tools
- Ideal Gas Isothermal Work Ratio
For nonnegative moles and positive temperature, gasConstant, initialVolume, and finalVolume return workByGas=moles*gasConstant*temperature*ln(finalVolume/initialVolume).
- Thermal Capacity Weight Share
Return capacity=mass*specificHeat and share=capacity/totalCapacity.