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Gas Specific Gravity and Ideal Gas Law Calculators

Universal Gas Law Calculations, Molecular Weights of Gases, and Specific Gravity

Gas Specific Gravity and Molecular Weight Conversion (free)

Select calculation:
Gas Specific Gravity, S: 
  Molecular Weight, M (g/mole): 
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Ideal Gas Calculator
Register to enable "Calculate" button.

Solve for: 
Select gas:   
Molecular Weight, M (g/mole): 
Absolute Pressure, P: 
Temperature, T: 
Density, d: 
Mass, m:   kg
Volume, V:   m3
Reload page (initial values) © LMNO Engineering, Research, and Software, Ltd.

Units: atm=atmosphere, C=Celsius, cm=centimeter, F=Fahrenheit, ft=foot, g=gram, kg=kilogram, m=meter, mm=millimeter, N=Newton, Pa=Pascal, psi=pound per square inch.

Equations for Gas Specific Gravity and Molecular Weight Conversion

S = M / Mair , where S=gas specific gravity, M=gas molecular weight, Mair=28.96443 g/mole (molecular weight of standard air - CRC, 1983).

The gas specific gravity calculation does not check for unreasonable inputs. Please enter positive values.

 

Equations for Ideal Gas Law Calculator (CRC, 1983)

Ideal Gas Equation

Ru = 8.3144126  N-m/mole-K

 

The ideal gas law calculation internally converts all user inputs to SI units, performs the calculation, then converts calculated values to user-desired units. All molecular weights are from CRC (1983). The molecular weight of air is computed from the volume fractions of the individual components in air given by CRC (1983):


Fractional Volumes of Components in Sea Level Dry Air (CRC, 1983)

Component N2 O2 Ar CO2 Ne He Kr Xe CH4 H2
Volume Fraction 0.78084 0.209476 9.34e-3 3.14e-4 1.818e-5 5.24e-6 1.14e-6 8.7e-8 2e-6 5e-7

Error Messages given by Ideal Gas calculation
"Inputs must be positive".  This is an initial check of user input. The only negative values that may be input are temperature expressed in oC or oF.
"T must be > 0".  This message will appear if temperature is entered in oR or K.
"T must be > -273.15".  This message will appear if temperature is entered in oC. -273.15 oC corresponds to absolute zero.
"T must be > -459.67".  This message will appear if temperature is entered in oF. -459.67 oF corresponds to absolute zero.

References
Chemical Rubber Company (CRC).  1983.  CRC Handbook of Chemistry and Physics. Weast, Robert C., editor.  63rd edition.  CRC Press, Inc.  Boca Raton, Florida.  USA.

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