Chloride ion function

In [PtCl2(C2H4)]2, the double bonds of the olefin molecules lie perpendicular to the plane that contains the Pt and Cl groups. In this bridged compound, two chloride ions function as... 

Chloride ion generally is a moderate nucleophile and a weak base. However, in the following dehydrohalogenation reaction, chloride ion functions as a base, removing a proton to bring about elimination of the elements of HCl. 

A chloride ion functions as a nucleophile and attacks the carbonyl group... 

Accuracy and Interpretation of Measured pH Values. The acidity function which is the experimental basis for the assignment of pH, is reproducible within about 0.003 pH unit from 10 to 40°C. If the ionic strength is known, the assignment of numerical values to the activity coefficient of chloride ion does not add to the uncertainty. However, errors in the standard potential of the cell, in the composition of the buffer materials, and ia the preparatioa of the solutioas may raise the uacertaiaty to 0.005 pH unit. 

Chlorine dioxide gas is a strong oxidizer. The standard reversible potential is determined by the specific reaction chemistry. The standard potential for gaseous CIO2 in aqueous solution reactions where a chloride ion is the product is —1.511 V, but the potential can vary as a function of pH and concentration (26) ... 

Although it is conceivable that the nucleophilic chloride ion initiates the attack, much experience supports the classification of (1-4) as an electrophilic reaction. Of course, if is the attacking electrophile, the double bond must be functioning as a nucleophile.] Equation (1-5) shows an AdN reaction. 

The formation of 120 can be explained by attack of chloride ion at C-6 (rather than the more hindred endo side at C-3) as depicted in the intermediate 126, with concomitant migration of the ketal function to the 3,5-position. This procedure provides a convenient route to 6-substituted D-glucose derivatives from the readily accessible 49. Since rotation about the C-5—0 bond is required for the migration of the ketal, the reaction most likely is not of a concerted nature and may proceed via 126a-126b. 

Some commercial electrodes are supplied with a double junction. In such arrangements, the electrode depicted in Fig. 15.1(h) is mounted in a wider vessel of similar shape which also carries a porous disc at the lower end. This outer vessel may be filled with the same solution (e.g. saturated potassium chloride solution) as is contained in the electrode vessel in this case the main function of the double junction is to prevent the ingress of ions from the test solution which may interfere with the electrode. Alternatively, the outer vessel may contain a different solution from that involved in the electrode (e.g. 3M potassium nitrate or 3M ammonium nitrate solution), thus preventing chloride ions from the electrode entering the test solution. This last arrangement has the disadvantage that a second liquid junction potential is introduced into the system, and on the whole it is preferable wherever possible to choose a reference electrode which will not introduce interferences. 

Since the rate was independent of acidity even over the range where H0 and pH differ, and the concentration of free amine is inversely proportional to the acidity function it follows that the rate of substitution is proportional to h0. If the substitution rate was proportional to [H30+] then a decrease in rate by a factor of 17 should be observed on changing [H+] from 0.05 to 6.0. This was not observed and the discrepancy is not a salt effect since chloride ion had no effect. Thus the rate of proton transfer from the medium depends on the acidity function, yet the mechanism of the reaction (confirmed by the isotope effect studies) is A-SE2, so that again correlation of rate with acidity function is not a satisfactory criterion of the A-l mechanism. 

Fig. 2.—The electron distribution D = 4irrlp as a function of r for the sodium ion and the chloride ion.

Fig. 3.—The theoretical and the experimental electron distribution (as a function of the distance from the nucleus) for the sodium and the chloride ion.

Chromatograms demonstrating the simultaneous use of all three detector functions are shown in figure 22. It is seen that the anthracene is clearly picked out from the mixture of aromatics by the fluorescence detector and the chloride ion, not shown at all by the UV adsorption or fluorescence detectors, clearly shown by the electrical conductivity detector. 

The tertiary amines 303 and the acid chlorides 304 (X = Cl) initially formed acylammonium salts 305, which underwent a von Braun type degradation by an attack of the nucleophilic chloride ion at the allyl system to give allyl chlorides 306/307 and carboxylic acid amide functions. 

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