Search results
Results from the WOW.Com Content Network
Of all the radiation-based chemical reactions that have been studied, the most important is the decomposition of water. [1] When exposed to radiation, water undergoes a breakdown sequence into hydrogen peroxide, hydrogen radicals, and assorted oxygen compounds, such as ozone, which when converted back into oxygen releases great amounts of energy.
The self-ionization of water (also autoionization of water, autoprotolysis of water, autodissociation of water, or simply dissociation of water) is an ionization reaction in pure water or in an aqueous solution, in which a water molecule, H 2 O, deprotonates (loses the nucleus of one of its hydrogen atoms) to become a hydroxide ion, OH −.
Hydrogen peroxide is a chemical compound with the formula H 2 O 2.In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water.It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
In the wash, both compounds dissolve in the water. When dissolved in water, the persalt releases hydrogen peroxide (e.g. from sodium percarbonate): 2Na 2 CO 3 ∙3H 2 O 2 → 2Na 2 CO 3 + 3H 2 O 2. In a basic wash solution, hydrogen peroxide loses a proton and is converted to the perhydroxyl anion: H 2 O 2 ⇌ H + + HO 2 −
In thermolysis, water molecules split into hydrogen and oxygen. For example, at 2,200 °C (2,470 K; 3,990 °F) about three percent of all H 2 O are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H 2, O, O 2, and OH. Other reaction products like H 2 O 2 or HO 2 remain minor. At the very high temperature of 3,000 ...
The reaction, using H 2 O 2 for the formation of ·OH, is carried out in an acidic medium (2.5-4.5 pH) [9] and a low temperature (30 °C - 50 °C), [10] in a safe and efficient way, using optimized catalyst and hydrogen peroxide formulations.
Hydrogen gas released in this way can be used as hydrogen fuel, but must be kept apart from the oxygen as the mixture would be extremely explosive. Separately pressurised into convenient 'tanks' or 'gas bottles', hydrogen can be used for oxyhydrogen welding and other applications, as the hydrogen / oxygen flame can reach approximately 2,800°C.
Water is fundamental to both photosynthesis and respiration. Photosynthetic cells use the sun's energy to split off water's hydrogen from oxygen. [107] In the presence of sunlight, hydrogen is combined with CO 2 (absorbed from air or water) to form glucose and release oxygen. [108]