Activity series and

In this section, you learned to define and recognize redox reactions, and to write oxidation and reduction half-reactions. In Investigation 10-A, you observed the connection between the metal activity series and redox reactions. However, thus far, you have only worked with redox reactions that involve atoms and ions as reactants or products. In the next section, you will learn about redox reactions that involve covalent reactants or products. 

But if a chemist placed metallic silver into hydrochloric acid, nothing would happen. That is because silver is not as reactive as hydrogen. It is below hydrogen in the activity series and it cannot replace the hydrogen in the reaction ... 

The effect of polarity on vinyl monomer copolymerization has long been recognized and is a major factor in the Q, e scheme and copolymerization theory. Mayo, Lewis, and Walling tabulated a number of vinyl monomers into an average activity series and an electron donor-acceptor series (62). The activity series showed the effect of substituents on the ease with which an ethylene derivative reacted with an average radical and on stabilizing the radical which was formed thereby. The electron donor-acceptor series indicated the ability of the substituents to serve as donors or acceptors in radical-monomer interactions. It is significant that in both series the dominant factor is the radical-monomer interaction. 

You can use Figure 10-10 to predict whether or not certain reactions will occur. A specific metal can replace any metal listed below it that is in a compound. It caimot replace any metal listed above it. For example, you saw in Figure 10-9 that copper atoms replace silver atoms in a solution of silver nitrate. However, if you place a silver wire in aqueous copper(II) nitrate, the silver atoms will not replace the copper. Silver is listed below copper in the activity series and no reaction occurs. The letters NR (no reaction) are commonly used to indicate that a reaction will not occur. 

Predict the outcome of the reactions represented by the following equations by using the activity series, and balance the equations. 

If you have samples of alloys that contain high percentages of metals, then often the best way to separate and quantitate these metals is to selectively electroplate them. Copper and nickel are on opposite sides of hydrogen in the activity series and, hence, can be separated electrically by control of the pH. 

One of the early successes in the kinase CBP was the establishment of a core panel of kinases against which all compounds of interest were screened, and from which surrogates were used to form cocrystals and develop SAR. Within 1 year, active compounds were found for the kinases, including 21 active series, and 9 lead compounds were selected. 

Of these metals, copper and magnesium are furthest apart in the activity series. This combination of electrodes gives the highest cell potential. Lead and iron are the closest in the activity series and give the lowest voltage. Hence, the further apart the two metals are in the activity series, the higher the cell potential. Table 9.8 Selected voltaic cells and cell... 

The distinction between the activity series and the electrochemical series can be illustrated by adding lithium and potassium to water. Lithium reacts more slowly with water than potassium does, despite the former having a more negative electrode potential. The reaction between lithium and water to form lithium ions is more thermodynamically fevourable than that between potassium and water, but the reaction is slower. 

At the cathode, copper(ii) ions are discharged in preference to hydrogen ions because hydrogen is below copper in the activity series, and so the cathode becomes plated with copper. 

The remaining questions include all types of reactions discussed in this chapter. Use the activity series and solubility guidelines to predict whether redox or precipitation reactions will take place. If a reaction will take place, write the net ionic equation if not,... 

Aluminum is above lead in the activity series and therefore is more active. It will replace lead in its compounds in water solution. A single-replacement reaction will take place to form the nitrate of aluminum, a group 3A metal. The skeleton equation is shown below. 

Even ia 1960 a catalytic route was considered the answer to the pollution problem and the by-product sulfate, but nearly ten years elapsed before a process was developed that could be used commercially. Some of the eadier attempts iacluded hydrolysis of acrylonitrile on a sulfonic acid ion-exchange resia (69). Manganese dioxide showed some catalytic activity (70), and copper ions present ia two different valence states were described as catalyticaHy active (71), but copper metal by itself was not active. A variety of catalysts, such as Umshibara or I Jllmann copper and nickel, were used for the hydrolysis of aromatic nitriles, but aUphatic nitriles did not react usiag these catalysts (72). Beginning ia 1971 a series of patents were issued to The Dow Chemical Company (73) describiag the use of copper metal catalysis. Full-scale production was achieved the same year. A solution of acrylonitrile ia water was passed over a fixed bed of copper catalyst at 85°C, which produced a solution of acrylamide ia water with very high conversions and selectivities to acrylamide. 

Astemi2ole (10) has further been modified into a series of 4-phenylcyclohexylamine compounds, resulting in the synthesis of cabastine, for example. Cabastine is a highly active compound and its geometric isomers are also active, demonstrating the stereoselectivity of histamine receptors toward chiral ligands. The > S, 4 R-levo antipode of cabastine was the most active, and therefore this isomer, levocabastine (13), has been chosen for further development. Because of high potency, levocabastine has been developed for topical appHcation such as eye drops and nasal spray. 

Order of thermal stabiUty as determined by differential thermal analysis is sebacic (330°C) > a2elaic = pimelic (320°C) > suberic = adipic = glutaric (290°C) > succinic (255°C) > oxahc (200°C) > malonic (185°C) (19). This order is somewhat different than that in Table 2, and is the result of differences in test conditions. The energy of activation for decarboxylation has been estimated to be 251 kj/mol (60 kcal/mol) for higher members of the series and 126 kJ/mol (30 kcal/mol) for malonic acid (1). 

Thorinm-232 is the only non-radiogenic thorium isotope of the U/Th decay series. Thorinm-232 enters the ocean by continental weathering and is mostly in the particulate form. Early measurements of Th were by alpha-spectrometry and required large volume samples ca. 1000 T). Not only did this make sample collection difficult, but the signal-to-noise ratio was often low and uncertain. With the development of a neutron activation analysis " and amass spectrometry method " the quality of the data greatly improved, and the required volume for mass spectrometry was reduced to less than a liter. Surface ocean waters typically have elevated concentrations of dissolved and particulate 17,3 7,62... 

As summarized in the following tabulation, the relative rates of piperidino-debromination of the halo-l-nitronaphtholenes (data from Table XII, numbered to show relation to quinolines) provide a good confirmation of the relation of induction (ind.) to resonance activation (res.) and of the extent of transmission of activation to an adjoining ring. Here again, as in the quinoline series, the 8-isomer (346) is more reactive than its resonance-activated 5-bromo isomer (345) and its inductively activated 3- and 6-bromo isomers (351 and... 

Thus the activity of the methyl groups in this reaction decreases in the series C-4 > C-5 > C-3. This may be considered as evidence of the inhibiting effect of the nitrogen hetero atom on the radical substitution in methyl groups at C-3 and, to a lesser extent, at C-5 (compare the effect of the heterocyclic nitrogen in the pyridine and azole series ) and of a similar effect of the electron-accepting substituents in the 4-position on the methyl group at C-5. 

Some hydroxamic acids of the isoxazole series also display a marked antituberculosis activity. The penicillin derivatives, acylated with isoxazole carboxylic acids possess an antibacterial activity similar to that of penicillin, against resistant species.Among other isoxazole derivatives possessing activity one should especially mention the sulfonamides of this series, and 4-hydroxyiminoisoxazol-5-... 

Pickard and Littlebury have carried out a series of investigations on the separation of the optically active borneols and isobomeols, which is of particular interest, as the method of separation can probably be applied to various other similar bodies. This method depends on the... 

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