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The main polycarbonate material is produced by the reaction of bisphenol A (BPA) and phosgene COCl 2. The overall reaction can be written as follows: The first step of the synthesis involves treatment of bisphenol A with sodium hydroxide, which deprotonates the hydroxyl groups of the bisphenol A. [6] (HOC 6 H 4) 2 CMe 2 + 2 NaOH → Na 2 (OC 6 ...
These fuel cells produce electricity by removing an electron from a hydrogen atom, pushing the charged hydrogen atom through the ceramic membrane, and returning the electron to the hydrogen on the other side of the ceramic membrane during a reaction with oxygen. The reaction of many proposed fuels in PCFCs produce electricity and heat, the ...
Extremely expensive materials were used and the fuel cells required very pure hydrogen and oxygen. Early fuel cells tended to require inconveniently high operating temperatures that were a problem in many applications. However, fuel cells were seen to be desirable due to the large amounts of fuel available (hydrogen and oxygen). [citation needed]
A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids , the conceptual anhydrides of carbonic acid , or polymers of carbon dioxide .
A fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen) [1] into electricity through a pair of redox reactions. [2] Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen (usually from air) to sustain the chemical reaction ...
Rather than combustion, organisms rely on elaborate sequences of electron-transfer reactions, often coupled to proton transfer. The direct reaction of O 2 with fuel is precluded by the oxygen reduction reaction, which produces water and adenosine triphosphate. Cytochrome c oxidase affects the oxygen reduction reaction by binding O 2 in a heme ...
Oxygen, usually in the form of air, is supplied to the cathode and combines with the electrons and the hydrogen ions to produce water. The reactions at the electrodes are as follows: Anode reaction: 2H 2 → 4H + + 4e − Cathode reaction: O 2 + 4H + + 4e − → 2H 2 O Overall cell reaction: 2H 2 + O 2 → 2H 2 O + heat + electrical energy
This plastic bucket has been used as an open-air flowerpot for some years. Photodegradation has made it brittle, causing part of it to break off when the bucket was moved. In polymer chemistry, photo-oxidation (sometimes: oxidative photodegradation) is the degradation of a polymer surface due to the combined action of light and oxygen. [1]