Read about this experiment in Fourteen Weeks in Chemistry.
- The density of carbon dioxide @ STP is 44.0g/22.4 L = 1.99 g/L
- The density of air (80% N2 20% O2 ) = 1.29 g/L
The density difference is significant.
CO2 is a common industrial gas. Care must be taken so that someone working with it doesn't drown in the gas. Each year people are killed in confined spaces that have become saturated with carbon dioxide.
Methane is flammable and has a density that is less than air.
- The density of methane, CH4 @ STP is 16.0g/22.4 L = 0.715 g/L.
- The density of air (80% N2 20% O2 ) = 1.29 g/L
The opposite of carbon dioxide.
Methane is commonly called natural gas and is the main gas used for energy in the US.
Sulfur hexafluoride is one of the densest gases known.
- The density of sulfur hexafluoride, SF6 @ STP is 146g/22.4 L = 6.52 g/L
- The density of air (80% N2 20% O2 ) = 1.29 g/L
Video from Bohn University
Substances with large molar masses tend to be liquids, but the molecular symmetry and low number of fluorine electrons allow SF6 to have small enough intermolecular forces to be a gas at room temperature.
