Chemistry of Gases and Applications

 Storage of any gas is generally done at high pressure so, as to store it efficiently in a closed vessel. Temperature is never raised because high temperature may cause the vessel to burst. 

Hydrogen gas produced from natural gas is used in the production of urea, which is widely used as a fertiliser. 

The temperature and pressure conditions required for the formation of natural gas are very difficult to be provided in the laboratory. Moreover, it takes a long time to be formed. That is why it cannot be prepared in the laboratory.

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Oxygen is the most abundant element in Earth's crust, comprising approximately 46-47% by weight. This is primarily due to the abundance of oxygen-containing minerals like silicates and oxides that make up most of the crust's composition.

Hydrogen is the lightest gas with the lowest atomic mass (1 amu) among all gases. It is the first element in the periodic table and forms H2 molecules in its gaseous state.

The gas which caused Bhopal gas tragedy of 1984 was methyl iso-cyanate.

Nitrous oxide (N2O) is commonly called 'laughing gas' because it induces euphoria and laughter when inhaled. It was discovered by Joseph Priestley in 1772 and is used as an anesthetic and in food preparation (whipped cream dispensers).

Argon is the third most abundant gas in Earth's atmosphere (approximately 0.93% by volume), making it the most abundant noble/inert gas. Helium, neon, and krypton are also inert gases but exist only in trace amounts - helium at about 0.0005%, neon at 0.0018%, and krypton at about 0.0001%. Argon's abundance comes from the radioactive decay of potassium-40 in Earth's crust.

The Krebs cycle involves multiple oxidation steps where acetyl-CoA is oxidized to CO2, with NAD+ and FAD being reduced to NADH and FADH2. The cycle completes when the original oxaloacetate is regenerated through a series of oxidation reactions.

Marsh gas is the common name for methane (CH4) because it's produced by anaerobic decomposition of organic matter in marshes and swamps. H2S is hydrogen sulfide (rotten egg gas), C2H4 is ethene, and C2H2 is acetylene - none of which are called marsh gas.

Heating sodium acetate with sodalime produces methane (CH4) via decarboxylation, not ethylene, ethane, or acetylene. This is a classic laboratory reaction for methane preparation.

Early Earth's atmosphere was reducing in nature, composed mainly of hydrogen along with methane, ammonia, and water vapor. Free oxygen only appeared later after photosynthesis began. Options like ammonia and methane were present, but hydrogen is considered the primary component in the primitive reducing atmosphere model.