Archive | Diatomic gases


Chlorine, often in the form of calcium hypochlorite, Ca(OCl)2, is added to swimming pools to kill microorganisms.  The acidic form of hypochlorite, hypochlorous acid (HOCl), is the effective antibiotic: OCl– + H3O+ –> HOCl + H2O This means that pool water must be kept acidic enough to allow HOCl to form, but not too acidic (you don’t […]


When a fluorine atom gains an electron, it becomes a fluoride ion: F + electron –> F– Teeth are often treated with fluoride.  This is because when fluoride substitutes for hydroxide in hydroxyapatite (the mineral in teeth), a stronger mineral results: Ca10(PO4)6(OH)2 + 2 F– –> Ca10(PO4)6(F)2 + 2 OH– next element           […]


Oxygen is necessary for the combustion (burning) of carbon-containing fuels.  For example, the combustion of methane is represented by: CH4 (g) + 2 O2 (g) –> CO2 (g) + 2 H2O (g) Combustion of carbon-containing fuels is the primary source of energy for a variety of processes on earth.  Oxygen is also required for the […]


Nitrogen is found in large amounts in fertilizer.  One simple example of a nitrogen-containing explosive is nitrogen triiodide (NI3).   Nitrogen triiodide, like many explosives, forms N2 gas upon detonation: 2 NI3 (s) –> 3 I2 (g) + N2 (g) The formation of N2 (g) releases almost a megajoule per mole.  This energy release upon the […]


Hydrogen is the most abundant element in the universe.  On Earth, it is usually found as a diatomic gas (H2 ).  The reaction of hydrogen gas with oxygen gas to form water releases a tremendous amount of energy: 2H2 (g) + O2 (g) –> 2 H2 O (l) + Energy As a result of the […]