High energy bond

A phosphoanhydrlde bond or other high-energy hond (commonly denoted by ) is not Intrinsically different from other covalent bonds. High-energy bonds simply release especially large amounts of energy when broken by addition of water (hydrolyzed). For Instance, the AG" for hydrolysis of a phosphoanhydrlde bond in ATP (—7.3 kcal/mol) is more than three times the AG" for hydrolysis of the phosphoester bond (red) in glycerol 3-phosphate (—2.2 kcal/mol) ... 

The heats of formation of the gaseous atoms, 4, are not very different clearly, it is the change in the bond dissociation energy of HX, which falls steadily from HF to HI, which is mainly res ponsible for the changes in the heats of formation. 6. We shall see later that it is the very high H—F bond energy and thus the less easy dissoeiation of H—F into ions in water which makes HF in water a weak aeid in comparison to other hydrogen halides. 

Rosenbluth algorithm can also be used as the basis for a more efficient way to perform ite Carlo sampling for fully flexible chain molecules [Siepmann and Frenkel 1992], ch, as we have seen, is difficult to do as bond rotations often give rise to high energy rlaps with the rest of the system. 

The cumulated double bonds of an allenic system are of relatively high energy The heat of hydrogenation of allene is more than twice that of propene... 

ATP IS the mam energy storing molecule for practically every form of life on earth We often speak of ATP as a high energy compound and its P—O bonds as high energy bonds This topic is discussed m more detail m Sections 28 4 and 28 5... 

Homogeneous Sonochemistry Bond Breaking and Radical Formation. The chemical effect of ultrasound on aqueous solutions have been studied for many years. The primary products are H2O2 there is strong evidence for various high-energy intermediates, including HO2,... 

It is estimated that mote than 25 x 10 different potentially toxic OP esters can be made using Schrader s classic (27) formula for effective phosphorylating agents, (39), where R and are short-chain alkyl, alkoxy, alkylthio, or alkylamino groups, and X is a displaceable moiety with a high energy P-bond such as E or acyl anhydride, and the pentavalent phosphoms atom is bonded to oxygen or sulfur. 

PhenylPhosphorothioa.te Esters. These are the most widely used OP iasecticides and iacorporate pseudoanhydride high energy phosphate bonds between phosphoric acid and phenols that are present ia the activated P=0 state. 

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