Process, Test, Instrumentation and Controls
Representatives for Maryland & Virginia

OFFICES TO SERVICE YOUR NEEDS

Main Office
10940 Beaver Dam Rd
Hunt Valley, MD  21030
Ph:  410-666-3200
Fx:  410-666-3631

Central VA Office
10993 Richardson Rd #13
Ashland, VA  23005
Ph:  804-752-3450
Fx:  804-752-3451

Tidewater VA Office
4402 Edwin Rd
Portsmouth, VA  23703
Ph:  757-686-1777
Fx:  757-686-9333

Western VA Office
Wytheville, VA
Ph: 540-639-3825
Fx: 410-666-3631

Gas Properties

 

(Approximate Values Calculated at 68°F and 147 psia)

cp = specific heat at constant pressure
cv = specific heat at constant volume 

 

Name of Gas Chemical Formula or Symbol Approx. Molecular Weight
M		 Weight Density, Pounds per Cubic Foot
p		 Specific Gravity Relative to Air
Sg		 Individual Gas Constant
R		 Specific Heat at Room Temperature Btu/Lb °F Heat Capacity per Cubic Foot k
equal to
cp/cv
cp cv cp cv
Acetylene (ethyne) C2H2 26.0 .0682 0.907 59.4 0.350 0.269 .0239 .0184 1.30
Air -- 29.0 .0752 1.000 53.3 0.241 0.172 .0181 .0129 1.40
Ammonia H3N 17.0 .0448 .0596 91.0 0.523 0.396 .0234 .0178 1.32
Argon Ar 39.9 .1037 1.379 38.7 0.124 0.074 .0129 .0077 1.67
Butane C4H10 58.1 .1554 2.067 26.5 0.395 0.356 .0614 .0553 1.11
Carbon dioxide CO2 44.0 .1150 1.529 35.1 0.205 0.158 .0236 .0181 1.30
Carbon monoxide CO 28.0 .0727 0.967 55.2 0.243 0.173 .0177 .0126 1.40
Chlorine Cl 70.9 .1869 2.486 21.8 0.115 0.086 .0215 .0162 1.33
Ethane C2H6 30.0 .0789 1.049 51.5 0.386 0.316 .0305 .0250 1.22
Ethylene C2H4 28.0 .0733 0.975 55.1 0.400 0.329 .0293 .0240 1.22
Helium He 4.0 .01039 0.1381 386.3 1.250 0.754 .0130 .0078 1.66
Hydrogen chloride HCl 36.5 .0954 1.268 42.4 0.191 0.135 .0182 .0129 1.41
Hydrogen H 2.0 .00523 0.0695 766.8 3.420 2.426 .0179 .0127 1.41
Hydrogen sulphide H2S 34.1 .0895 1.190 45.2 0.243 0.187 .0217 .0167 1.30
Methane CH4 16.0 .0417 0.554 96.4 0.593 0.449 .0247 .0187 1.32
Methyl chloride CH3Cl 50.5 .1342 1.785 30.6 0.240 0.200 .0322 .0268 1.20
Natural gas -- 19.5 .0502 0.667 79.1 0.560 0.441 .0281 .0221 1.27
Nitric oxide NO 30.0 .0780 1.037 51.5 0.231 0.165 .0180 .0129 1.40
Nitrogen N 28.0 .0727 0.967 55.2 0.247 0.176 .0180 .0127 1.41
Nitrous oxide N2O 44.0 .1151 1.530 35.1 0.221 0.169 .0254 .0194 1.31
Oxygen O 32.0 .0831 1.105 48.3 0.217 0.155 .0180 .0129 1.40
Propane C3H8 44.1 .1175 1.562 35.0 0.393 0.342 .0462 .0402 1.15
Propene (propylene) C3H6 42.1 .1091 1.451 36.8 0.358 0.314 .0391 .0343 1.14
Sulphur dioxide SO2 64.1 .1703 2.264 24.0 0.154 0.122 .0262 .0208 1.26