Redox Reactions: Oxidation and Reduction
biology photosynthesis process Photosynthesis Light Reaction
In notating redox reactions, chemists typically write out the electrons explicitly:This half-reaction says that we have solid copper (with no charge) being oxidized (losing electrons) to form a copper ion with a plus 2 charge.
There are three definitions you can use for oxidation:
Both carbon-containing molecules have the same oxygen content, but the formation of the formaldehyde is seen to be oxidation because hydrogens are lost. The formation of H2 is a reduction process as the two released hydrogens get together.
Redox Reactions Flashcards | Quizlet
Both the LHC and the reaction centers are membrane bound structures but there are no chloroplasts in the purple photosynthetic bacteria. The electron transfer processes occur within the cell membrane and the overall process is a cyclic one (i.e., there is no net oxidation-reduction). Protons are transferred across the membrane, from the cytoplasmic side to the outside, establishing a proton gradient whose dissipation drives ATP synthesis. A similar situation holds for the cyanobacteria and plants, but in these organisms, the process occurs in chloroplasts and the overall reaction is not a cyclic one.
Oxidation-Reduction Reactions: Redox
We'll look at a simpler example of photosynthesis first, and use it as an introduction to photosynthesis in plants and cyanobacteria (blue-green algae). Although the primary reactions of photosynthesis take place at "photosynthetic reaction centers," the first level of interaction of light with an organism that carries out photosynthesis is at an assembly of chlorophyll molecules that "harvest" light (the "light-harvesting complex"). Such an assembly results in a greater chance that photons will be captured and, because of the strategic arrangement of the individual chlorophyll and other accessory light-absorbing molecules, the transfer of energy to the photosynthetic reaction center is very fast (-10 s) and very efficient (>90%).
It involves oxidation/reduction reactions ..
Lewis structures can play a vital role in understanding oxidation-reduction reactionswith complex molecules. Consider the following reaction, for example, which is used in theBreathalyzer to determine the amount of ethyl alcohol or ethanol on the breath ofindividuals who are suspected of driving while under the influence.