Chemistry of Gases and Applications

Oxygen is the oxidizing agent required for combustion (burning). Without oxygen, most fires cannot sustain themselves.

Manganese bronze is a type of brass used in marine engineering and aircraft building due to its strength and corrosion resistance. Other options are incorrect or imprecise.

Normal air consists primarily of nitrogen, oxygen, argon, and trace amounts of other gases. Chlorine is a toxic gas not found in normal atmospheric samples.

Helium is preferred over hydrogen in hot air balloons because hydrogen can readily catch fire and helium is lighter than any of the other rare gases.

Nitrogen is used as a cooling agent in refrigeration.

The transformation of atmospheric nitrogen into a usable form is known as nitrogen fixation.

The Sun is composed primarily of hydrogen (about 73 percent) and helium (about 25 percent), with trace amounts of other elements.

Oxygen is not a greenhouse gas because it does not absorb infrared radiation. Greenhouse gases include carbon dioxide, methane, and water vapor.

Methane is commonly referred to as marsh gas because it is produced in marshes by the anaerobic decomposition of organic matter.

Freon is used in household refrigerator.

Ammonia (R-717) is a common refrigerant gas used in industrial refrigeration systems due to its high efficiency and thermodynamic properties.

Nitrogen (N2) makes up approximately 78 percent of Earth's atmosphere, making it the most abundant gas. Oxygen (O2) follows at about 21 percent.

Nitrogen (N2) makes up approximately 78 percent of Earth's atmosphere, making it the most abundant gas in the air.

Nitrogen fixation is the process of converting atmospheric nitrogen into compounds like ammonia or nitrates. While the term 'nitrogenation' is not standard, it is the only option here referring to the fixation process.

Ammonia consists of one nitrogen atom covalently bonded to three hydrogen atoms, represented by the chemical formula NH3.