Chapter SPS 343 Appendix

Register December 2011 No. 672

Chapter SPS 343

APPENDIX

The material contained in this appendix is for clarification and general information only.

Physical Properties of Ammonia

Molecular symbol   NH3

Molecular weight   17.031

Boiling point at one atmosphere*   -28°F

Melting point one atmosphere*   -107.9°F

Critical temperature   271.4°F

Critical pressure   1657 psia

Latent heat at -28°F and one atmosphere*   589.3 Btu/lb

Relative density of vapor compared to dry air at 32°F and one atmosphere*   0.5970

Vapor density at -28°F and one atmosphere*   0.05555 lb/ft3

Specific gravity of liquid at -28°F compared to water at 39.2°F   0.6819

Weight per gallon of liquid at -28°F   5.69 lbs/gallon

Liquid density at -28°F and one atmosphere   42.57 lbs/ft3

Specific volume of vapor at 32°F and one atmosphere   20.78 ft3/lb

Flammable limits by volume in air at atmospheric pressure   16% to 25%

Ignition Temperature (in a standard quartz container)   1562° F

Specific Heat, Gas, at 59°F and one atmosphere*

  at constant pressure, Cp   0.5232 Btu/lb °F

  at constant volume, Cv   0.3995 Btu/lb °F

*One atmosphere = 14.7 psia