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Making of hydrogen

There are both macroscopic effects of ions on the dynamics of electrolyte solutions relative to pure water and microscopic effects on the dynamics of the water molecules themselves. The former include the effects of ions on the fluidity of the solution as a whole, which is the reciprocal of its viscosity, and on the self-diffusion of the water. The latter pertain to the movements of individual water molecules their mutual orientations, the rate of breaking or making of hydrogen bonds, etc. Such effects have been measured experimentally, as discussed in Sects. 3.1.1-3.1.5, and are complemented by computer simulations in Sect. 3.1.6. [Pg.100]

Purification of refinery gases by elimination of hydrogen sulfide as well as Claus units for sulfur recovery began to make their appearance. [Pg.406]

The literature states that if one uses ice cold, concentrated sulfuric acid on a terminal alkene (a.k.a. allylbenzene) an alcohol (OH) intermediate will form Markovnikoviy on the secondary carbon (don t ask). What does this mean Let s take an example. Say one has some elemi oil and wants that elemicin that is in it. What one can do is chili, say, 500mLs of the oil to freezing and do the same for about 100-200mLs of concentrated sulfuric acid (at least 90% cone.). Next, one just mixes the two together for about 5 min. What will happen is that the cold H2SO4 will make a hydrogen... [Pg.50]

The electrophilic character of boron is again evident when we consider the oxida tion of organoboranes In the oxidation phase of the hydroboration-oxidation sequence as presented m Figure 6 11 the conjugate base of hydrogen peroxide attacks boron Hydroperoxide ion is formed m an acid-base reaction m step 1 and attacks boron m step 2 The empty 2p orbital of boron makes it electrophilic and permits nucleophilic reagents such as HOO to add to it... [Pg.254]

Fluorine addition to alkenes is a violent reaction difficult to control and accompa med by substitution of hydrogens by fluorine Vicinal diicxlides on the other hand tend to lose I2 and revert to alkenes making them an infrequently encountered class of compounds... [Pg.256]

There are two products that can be formed by syn addition of hydrogen to 2 3 dimethylbi cyclo[2 2 1] 2 heptene Write or make molecular models of their structures... [Pg.277]

The presence of an aldehyde function m their open chain forms makes aldoses reactive toward nucleophilic addition of hydrogen cyanide Addition yields a mixture of diastereo meric cyanohydrins... [Pg.1055]

The basic chemical premise involved in making synthetic natural gas from heavier feedstocks is the addition of hydrogen to the oil ... [Pg.74]

Mixtures of CO—H2 produced from hydrocarbons, as shown in the first two of these reactions, ate called synthesis gas. Synthesis gas is a commercial intermediate from which a wide variety of chemicals are produced. A principal, and frequendy the only source of hydrogen used in refineries is a by-product of the catalytic reforming process for making octane-contributing components for gasoline (see Gasoline and OTHER MOTOR fuels), eg. [Pg.415]

A wide range and a number of purification steps are required to make available hydrogen/synthesis gas having the desired purity that depends on use. Technology is available in many forms and combinations for specific hydrogen purification requirements. Methods include physical and chemical treatments (solvent scmbbing) low temperature (cryogenic) systems adsorption on soHds, such as active carbon, metal oxides, and molecular sieves, and various membrane systems. Composition of the raw gas and the amount of impurities that can be tolerated in the product determine the selection of the most suitable process. [Pg.428]

The mechanism of the tarmage is accepted to be largely one of replacement of the bound water molecules by the phenoHc groups of the tannin and subsequent formation of hydrogen bonds with the peptide bonds of the protein. The effect of this bonding is to make the leather almost completely biorefractive. [Pg.86]


See other pages where Making of hydrogen is mentioned: [Pg.382]    [Pg.107]    [Pg.180]    [Pg.29]    [Pg.211]    [Pg.180]    [Pg.171]    [Pg.528]    [Pg.614]    [Pg.616]    [Pg.617]    [Pg.125]    [Pg.382]    [Pg.107]    [Pg.180]    [Pg.29]    [Pg.211]    [Pg.180]    [Pg.171]    [Pg.528]    [Pg.614]    [Pg.616]    [Pg.617]    [Pg.125]    [Pg.60]    [Pg.33]    [Pg.1371]    [Pg.57]    [Pg.284]    [Pg.169]    [Pg.173]    [Pg.149]    [Pg.165]    [Pg.174]    [Pg.473]    [Pg.35]    [Pg.125]    [Pg.111]    [Pg.66]    [Pg.217]    [Pg.175]    [Pg.74]    [Pg.193]    [Pg.432]    [Pg.453]    [Pg.456]    [Pg.461]    [Pg.226]    [Pg.505]    [Pg.514]    [Pg.23]   


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Hydrogen, 28-29 making

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