Weight of 1 Liter of Various Gases measured under Standard Conditions

Acetylene1.1614
Air1.2923
Ammonia0.7617
Carbon dioxide1.9641
Carbon monoxide1.2499
Chlorine3.1650
Hydrocyanic acid1.2036
Hydrochloric acid1.6275
Hydrogen0.08984
Hydrosulphuric acid1.5211
Methane0.7157
Nitric oxide1.3410
Nitrogen1.2501
Nitrous oxide1.9677
Oxygen1.4285
Sulphur dioxide2.8596