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Usually a C-H bond is converted to a C-Cl bond. Photochlorination is carried out on an industrial scale. The process is exothermic and proceeds as a chain reaction initiated by the homolytic cleavage of molecular chlorine into chlorine radicals by ultraviolet radiation. Many chlorinated solvents are produced in this way.
Pc(Cu +) + Fd[ox] + hν → Pc(Cu 2+) + Fd[red] The cooperation between Photosystems I and II creates an electron and proton flow from H 2 O to NADP + , producing NADPH needed for glucose synthesis. This pathway is called the ' Z-scheme ' because the redox diagram from H 2 O to NADP + via P680 and P700 resembles the letter Z. [ 11 ]
The cyclic light-dependent reactions occur only when the sole photosystem being used is photosystem I. Photosystem I excites electrons which then cycle from the transport protein, ferredoxin (Fd), to the cytochrome complex, b 6 f, to another transport protein, plastocyanin (Pc), and back to photosystem I. A proton gradient is created across the ...
Photoexcitation is the first step in a photochemical process where the reactant is elevated to a state of higher energy, an excited state.The first law of photochemistry, known as the Grotthuss–Draper law (for chemists Theodor Grotthuss and John W. Draper), states that light must be absorbed by a chemical substance in order for a photochemical reaction to take place.
Industrial bleaching agents can be sources of concern. For example, the use of elemental chlorine in the bleaching of wood pulp produces organochlorines and persistent organic pollutants, including dioxins. According to an industry group, the use of chlorine dioxide in these processes has reduced the dioxin generation to under-detectable levels ...
In return, the zooxanthellae provide compounds that give energy to the coral through photosynthesis. [19] This relationship has allowed coral to survive for at least 210 million years in nutrient-poor environments. [19] Coral bleaching is caused by the breakdown of this relationship. [2] Coral bleaching in ecosystems is a complex dynamic.
The principal example is tert-butyl hypochlorite, which is a useful chlorinating agent. [3] Most hypochlorite salts are handled as aqueous solutions. Their primary applications are as bleaching, disinfection, and water treatment agents. They are also used in chemistry for chlorination and oxidation reactions.
Photosensitizers absorb light (hν) and transfer the energy from the incident light into another nearby molecule either directly or by a chemical reaction. Upon absorbing photons of radiation from incident light, photosensitizers transform into an excited singlet state.